"DR_REG_R10" in instr_shared.c and translate.c

Created by: egrimley

There are suspicious references to DR_REG_R10 in instr_shared.c and translate.c. Perhaps these should be dr_reg_stolen. It's hard to know as the code is not tested. Replacing the "#ifdef ARM" in instr_is_reg_spill_or_restore_ex() with "#if 0", or incrementing "value" just after it is set in translate_walk_restore(), causes no test to fail.

Does this code imply something missing for AArch64?