This is a fix to Bug 354797 which added the vbit test support for the

This is a fix to Bug 354797 which added the vbit test support for the
Power 8 instructions.

The patch for bug 354797 moved the declaration for rc outside of the
architecture #ifdef.  This results in an message about rc being unused
on architectures other then s390 and powerpc.  This commit eliminates
the issue by:

powerpc: move rc declaration into #ifdef for powerpc.
      Remove tab, put in missing break.

s390: remove rc declaration from inside case statement.  Put rc declaration
      before the switch statement but within the #ifdef for s390 so it will
      be declared for use in both case clauses.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15738