Lot of packages explicitly requires gcc now, but almost all of
the components needs it.
Always keep gcc in hand-range.
files/rpms/general: always installs the libxlst2-devel, not just on
RHEL 6, package recompile capability always handy and these are small
packages anyway.
Change-Id: Ia7d0e1938fb2453e3c02b979f99d6d179c6a24c6