Add NEON support to the NDK build system + docs

You can now define LOCAL_ARM_NEON to 'true' in your Android.mk
to indicate that a whole module must be compiled with NEON support.

Alternatively, use the .neon suffix when listing source files in
LOCAL_SRC_FILES to indicate that they should be built with NEON
support. E.g.:

  LOCAL_SRC_FILES := foo.c.neon bar.c zoo.c.arm.neon

Note that .arm.neon is supported, but .neon.arm is NOT.

Also added documentation in docs/CPU-ARM-NEON.TXT

Another patch will provide one or more sample applications
to demonstrate all of this.
9 files changed