Add pylint py3 portability checks for the metal repo

A lot of work has gone into making sure that StarlingX is python3
compatible. To ensure future compatibility, enable the python3
portability checks. Disable the checks that are raising errors.
Another set of commits will address the offending code.

Add following suppress warnings in pylint.rc:
- W1618: no-absolute-import
- W1624: indexing-exception

Story: 2006796
Task: 43282
Signed-off-by: Bernardo Decco <bernardo.deccodesiqueira@windriver.com>
Change-Id: I2fa69f9ea45a27f0c60eb05ea5d0f98b47da8945

pylint.rc

@@ -34,7 +34,87 @@ extension-pkg-whitelist=lxml.etree,greenlet
 # Enable the message, report, category or checker with the given id(s). You can
 # either give multiple identifier separated by comma (,) or put this option
 # multiple time.
-#enable=
+#
+# Python3 checker:
+#
+# E1601: print-statement
+# E1602: parameter-unpacking
+# E1603: unpacking-in-except
+# E1604: old-raise-syntax
+# E1605: backtick
+# E1606: long-suffix
+# E1607: old-ne-operator
+# E1608: old-octal-literal
+# E1609: import-star-module-level
+# E1610: non-ascii-bytes-literal
+# E1611: invalid-unicode-literal
+# W1601: apply-builtin
+# W1602: basestring-builtin
+# W1603: buffer-builtin
+# W1604: cmp-builtin
+# W1605: coerce-builtin
+# W1606: execfile-builtin
+# W1607: file-builtin
+# W1608: long-builtin
+# W1609: raw_input-builtin
+# W1610: reduce-builtin
+# W1611: standarderror-builtin
+# W1612: unicode-builtin
+# W1613: xrange-builtin
+# W1614: coerce-method
+# W1615: delslice-method
+# W1616: getslice-method
+# W1617: setslice-method
+# W1618: no-absolute-import
+# W1619: old-division
+# W1620: dict-iter-method
+# W1621: dict-view-method
+# W1622: next-method-called
+# W1623: metaclass-assignment
+# W1624: indexing-exception
+# W1625: raising-string
+# W1626: reload-builtin
+# W1627: oct-method
+# W1628: hex-method
+# W1629: nonzero-method
+# W1630: cmp-method
+# W1632: input-builtin
+# W1633: round-builtin
+# W1634: intern-builtin
+# W1635: unichr-builtin
+# W1636: map-builtin-not-iterating
+# W1637: zip-builtin-not-iterating
+# W1638: range-builtin-not-iterating
+# W1639: filter-builtin-not-iterating
+# W1640: using-cmp-argument
+# W1641: eq-without-hash
+# W1642: div-method
+# W1643: idiv-method
+# W1644: rdiv-method
+# W1645: exception-message-attribute
+# W1646: invalid-str-codec
+# W1647: sys-max-int
+# W1648: bad-python3-import
+# W1649: deprecated-string-function
+# W1650: deprecated-str-translate-call
+# W1651: deprecated-itertools-function
+# W1652: deprecated-types-field
+# W1653: next-method-defined
+# W1654: dict-items-not-iterating
+# W1655: dict-keys-not-iterating
+# W1656: dict-values-not-iterating
+# W1657: deprecated-operator-function
+# W1658: deprecated-urllib-function
+# W1659: xreadlines-attribute
+# W1660: deprecated-sys-function
+# W1661: exception-escape
+# W1662: comprehension-escape
+enable=E1603,E1609,E1610,E1602,E1606,E1608,E1607,E1605,E1604,E1601,E1611,W1652,
+       W1651,W1649,W1657,W1660,W1658,W1659,W1623,W1622,W1620,W1621,W1645,W1641,
+       W1624,W1648,W1625,W1611,W1662,W1661,W1650,W1640,W1630,W1614,W1615,W1642,
+       W1616,W1628,W1643,W1629,W1627,W1644,W1617,W1601,W1602,W1603,W1604,W1605,
+       W1654,W1655,W1656,W1619,W1606,W1607,W1639,W1618,W1632,W1634,W1608,W1636,
+       W1653,W1646,W1638,W1609,W1610,W1626,W1633,W1647,W1635,W1612,W1613,W1637
 
 # Disable the message, report, category or checker with the given id(s). You
 # can either give multiple identifier separated by comma (,) or put this option
@@ -58,9 +138,12 @@ extension-pkg-whitelist=lxml.etree,greenlet
 # R1724: Unnecessary "else" after "continue" (no-else-continue)
 # ** The following (W)arnings should be fixed:
 # W0703: Catching too general exception Exception (broad-except)
+# Disable Python3 checkers:
+#  W1618: no-absolute-import
+#  W1624: indexing-exception
 disable=C0103,C0114,C0302,C1801,
         R0205,R0902,R0912,R0913,R0915,R1705,R1723,R1724,
-        W0703
+        W0703, W1618, W1624
 
 #disable=C, R, fixme
 

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = linters,pep8
+envlist = linters,pep8,pylint
 minversion = 2.3
 skipsdist = True