Don't blindly use blx instruction without knowing whether the CPU supports it.

Review URL: http://codereview.chromium.org/67213

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1723 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/codegen-arm.cc

@@ -4574,7 +4574,7 @@ static void HandleBinaryOpSlowCases(MacroAssembler* masm,
     __ swi(swi_number);
 #else
     // Actually call the add routine written in C.
-    __ blx(r5);
+    __ Call(r5);
 #endif
     // Store answer in the overwritable heap number.
     __ pop(r4);