Clean up obsolete libm makefile cruft.

Change-Id: I52a80c182546168bc31ccc04d8bf815350dba28c
diff --git a/libm/Android.bp b/libm/Android.bp
index f22050e..08f1c66 100644
--- a/libm/Android.bp
+++ b/libm/Android.bp
@@ -1,6 +1,3 @@
-// ANDROIDMK TRANSLATION ERROR: unsupported conditional
-// ifneq ($(TARGET_USE_PRIVATE_LIBM),true)
-
 bionic_coverage = false
 
 //
@@ -522,13 +519,6 @@
         "-Wno-uninitialized",
         "-Wno-unknown-pragmas",
         "-fvisibility=hidden",
-
-        // Workaround the GCC "(long)fn -> lfn" optimization bug which will result in
-        // self recursions for lrint, lrintf, and lrintl.
-        // BUG: 14225968
-        "-fno-builtin-rint",
-        "-fno-builtin-rintf",
-        "-fno-builtin-rintl",
     ],
     conlyflags: ["-std=gnu11"],
 
@@ -541,6 +531,3 @@
     },
     stl: "none",
 }
-
-// ANDROIDMK TRANSLATION ERROR: endif from unsupported contitional
-// endif