Quick backend: rename target-specific #defines

Another step towards a single compiler.  The #include build mechanism
relies on macros with the same name to take on different values for
our various targets.  This CL prepends a target-specific string
(and exposes some needed by common code as functions rather than #defines).

Macros and #defines still available for use from target-dependent code,
but functions added for target independent use.  For example,
rRET0 for Arm becomes rARM_RET0 in target-dependent code, and
targetRegister(kRet0) in target-independent code.

No logic changes, other than adding functions to return previously #defined
values.  As of this CL, the primary target includes, xxxLIR.h, have no
macro collisions.

Change-Id: I5e11df844815b7d129b525a209dd7c46bd9a4a09
diff --git a/src/compiler/codegen/mips/Assemble.cc b/src/compiler/codegen/mips/Assemble.cc
index 9f8a686..e9dd219 100644
--- a/src/compiler/codegen/mips/Assemble.cc
+++ b/src/compiler/codegen/mips/Assemble.cc
@@ -677,16 +677,16 @@
           bits |= (value << encoder->fieldLoc[i].end);
           break;
         case kFmtDfp: {
-          DCHECK(DOUBLEREG(operand));
+          DCHECK(MIPS_DOUBLEREG(operand));
           DCHECK_EQ((operand & 0x1), 0U);
-          value = ((operand & FP_REG_MASK) << encoder->fieldLoc[i].start) &
+          value = ((operand & MIPS_FP_REG_MASK) << encoder->fieldLoc[i].start) &
               ((1 << (encoder->fieldLoc[i].end + 1)) - 1);
           bits |= value;
           break;
         }
         case kFmtSfp:
-          DCHECK(SINGLEREG(operand));
-          value = ((operand & FP_REG_MASK) << encoder->fieldLoc[i].start) &
+          DCHECK(MIPS_SINGLEREG(operand));
+          value = ((operand & MIPS_FP_REG_MASK) << encoder->fieldLoc[i].start) &
               ((1 << (encoder->fieldLoc[i].end + 1)) - 1);
           bits |= value;
           break;