Fix NativeARM; missed one file when backing out registerAllocTmp (r=me)

--HG--
extra : convert_revision : ec94ce9d044ee358a65c259a6151ce660122f813

js/src/nanojit/NativeARM.cpp

@@ -2457,7 +2457,8 @@ void
 Assembler::asm_jtbl(LIns* ins, NIns** table)
 {
     Register indexreg = findRegFor(ins->oprnd1(), GpRegs);
-    Register tmp = registerAllocTmp(GpRegs & ~rmask(indexreg));
+    Register tmp = registerAlloc(GpRegs & ~rmask(indexreg));
+    _allocator.addFree(tmp);
     LDR_scaled(PC, tmp, indexreg, 2);      // LDR PC, [tmp + index*4]
     asm_ld_imm(tmp, (int32_t)table);       // tmp = #table
 }