Extract runtime stub and update 2 runtime function

- Extract runtime stub from Runtime.c
- Remove __muldsi3 from Runtime.def.  Since it is declared static by
  llvm compiler-rt, we should not export them.
- Add alias for __aeabi_f2uiz because libgcc (for android) does not
  come with __aeabi_f2uiz.
diff --git a/lib/bcc/Runtime.def b/lib/bcc/Runtime.def
index e77bbf0..a300b5c 100644
--- a/lib/bcc/Runtime.def
+++ b/lib/bcc/Runtime.def
@@ -57,7 +57,7 @@
   DEF_GENERIC_RUNTIME(__aeabi_f2d)
   DEF_GENERIC_RUNTIME(__aeabi_f2iz)
   DEF_GENERIC_RUNTIME(__aeabi_f2lz)
-//DEF_GENERIC_RUNTIME(__aeabi_f2uiz) // TODO: Missing from libgcc.
+  DEF_GENERIC_RUNTIME(__aeabi_f2uiz)
   DEF_GENERIC_RUNTIME(__aeabi_f2ulz)
   DEF_GENERIC_RUNTIME(__aeabi_fadd)
   DEF_GENERIC_RUNTIME(__aeabi_fcmpeq)
@@ -187,7 +187,6 @@
 DEF_GENERIC_OR_VFP_RUNTIME(__muldf3)
 #if !defined(__i386__)
     DEF_LLVM_RUNTIME(__muldi3)
-    DEF_LLVM_RUNTIME(__muldsi3)
 #endif
 
 #ifndef ANDROID // no complex extension