Added parsing co-processor names starting with "cr"

Additional compliant GAS names for coprocessor register name
are enabled for all instruction with parameter MCK_CoprocReg:
LDC,LDC2,STC,STC2,CDP,CDP2,MCR,MCR2,MCRR,MCRR2,MRC,MRC2,MRRC,MRRC2

Patch by Andrey Kuharev.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211776 91177308-0d34-0410-b5e6-96231b3b80d8