Add test cases for PCMPxSTRx cases 0x0E, 0x34, 0x14, and reformat some
of the associated switch statements.  Pertains to #326469, #327639,
#328878 respectively.



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13986 a5019735-40e9-0310-863c-91ae7b9d1cf9