[PATCH] ARM: add support for QBIT

[Yi Kong]

Hi Saleem,

The patch is missing unit tests for the ACLE header.

Thanks,
Yi

================
Comment at: lib/Headers/arm_acle.h:110
@@ -109,1 +109,3 @@
 /* 9 DATA-PROCESSING INTRINSICS */
+
+/* 9.1.1 The Q (saturation) flag */
----------------
According to ACLE 2.0:
> ... intrinsics are available when __ARM_FEATURE_QBIT is defined

Please guard these functions with the corresponding flag.

http://reviews.llvm.org/D6107