Remove all TARGET_[ARM|X86|MIPS] #ifdefs

Two steps forward, one step back towards elimination of the
"#include" build model for target-specific compilers.  This CL
does some restructuring to eliminate all of the TARGET_xxx #ifdefs
and convert them to run-time tests.

Considerable work is still required to fully eliminate the multiple
builds.  In particular, much of the "common" codegen code relies on
macros defined by the target-specific [Arm|X86|Mips]Lir.h include file.

Next step is more restructuring to better isolate target-independent
code generation code.

Change-Id: If6efbde65c48031a48423344d8dc3e2ff2c4ad9d
diff --git a/src/compiler/codegen/arm/Assemble.cc b/src/compiler/codegen/arm/Assemble.cc
index ede3f61..759ffd3 100644
--- a/src/compiler/codegen/arm/Assemble.cc
+++ b/src/compiler/codegen/arm/Assemble.cc
@@ -1070,7 +1070,7 @@
           // Change the load to be relative to the new Adr base
           lir->operands[1] = baseReg;
           lir->operands[2] = 0;
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         } else {
           if ((lir->opcode == kThumb2Vldrs) ||
@@ -1101,7 +1101,7 @@
           /* operand[0] is src1 in both cb[n]z & CmpRI8 */
           lir->operands[1] = 0;
           lir->target = 0;
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         } else {
           lir->operands[1] = delta >> 1;
@@ -1126,7 +1126,7 @@
             }
           }
           lir->operands[0] = reg;
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         }
       } else if (lir->opcode == kThumbBCond || lir->opcode == kThumb2BCond) {
@@ -1138,7 +1138,7 @@
         delta = target - pc;
         if ((lir->opcode == kThumbBCond) && (delta > 254 || delta < -256)) {
           lir->opcode = kThumb2BCond;
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         }
         lir->operands[0] = delta >> 1;
@@ -1162,7 +1162,7 @@
           // Convert to Thumb2BCond w/ kArmCondAl
           lir->opcode = kThumb2BUncond;
           lir->operands[0] = 0;
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         } else {
           lir->operands[0] = delta >> 1;
@@ -1221,7 +1221,7 @@
           lir->opcode = kThumb2AddRRR;
           lir->operands[1] = rPC;
           lir->operands[2] = lir->operands[0];
-          oatSetupResourceMasks(lir);
+          oatSetupResourceMasks(cUnit, lir);
           res = kRetryAll;
         }
       } else if (lir->opcode == kThumb2MovImm16LST) {