- Add three more instruction contexts to EmulateInstruction:
eContextAdjustBaseRegister, eContextRegisterStore and
eContextWriteMemoryRandomBits.

- Implement a version of WriteBits32UnknownToMemory for writing to memory.

- Modify EmulateLDM, EmulateLDMDA, EmulateLDMDB and EmulateLDMIB to use the
eContextAdjustBaseRegister context when appropriate.

- Add code to emulate the STM/STMIA/STMEA Arm instruction.

llvm-svn: 125414