Build: Add support for specifying build variant in brunch/breakfast

This little modification allows specifying build variant in brunch/
breakfast commands. For example we can use "brunch i9300 user" to build
user variant instead of default userdebug.

When no extra argument is given, userdebug is default.

Change-Id: I935327252098ee74b34a815a023d2ac6b9a53a30
Apply correct, optimized mfpu compiler flag for ARMv7-A Cortex CPUs

For those ARMv7-A Cortex CPUs that can handle VFPv4 floating point,
We can set "-mfpu=neon-vfpv4" instead of generic "-mfpu=neon"
to gain extra performance improvements.

References :
 - GCC		: https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html
 - Cortex A15	: http://www.arm.com/products/processors/cortex-a/cortex-a15.php
 - Cortex A9	: http://www.arm.com/products/processors/cortex-a/cortex-a9.php
 - Cortex A8	: http://www.arm.com/products/processors/cortex-a/cortex-a8.php
 - Cortex A7	: http://www.arm.com/products/processors/cortex-a/cortex-a7.php
 - Cortex A5	: http://www.arm.com/products/processors/cortex-a/cortex-a5.php

Change-Id: Id8b1a251234014ecf7ffbc1ae14455ed1726e028
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
build: Clean up use of vendor/extra

 * extra_config.mk is not needed anymore
 * Include BoardConfigExtra.mk if available

Change-Id: Icd0db0852ceee5cb5c701c9a40b829e1f3ebd69e
build: qcom: Set QCOM_*_PATH variables for hardware/qcom-* projects

This consolidates a bunch of one-off logic scattered throughout the
code base.  Usage in Android.mk files is trivial:

At top level, use e.g. "ifeq ($(call my-dir),$(QCOM_AUDIO_PATH))".
This works for all variants, including non-variants (i.e. AOSP).

Within subdirs, use e.g. hardware/qcom/audio => $(QCOM_AUDIO_PATH)

Change-Id: Iee2497ea9a7efeb4ae9e861b84c532b19da7b69d
Merge commit '50d46bbc700c3fa72e965422de96aa666e5f0564' into cm-11.0-sgt7
Merge commit '8907b775376211e73a566e8c9ef65e5b76cba1af' into cm-11.0-sgt7

Conflicts:
	core/combo/arch/arm/armv7-a-neon.mk
Merge commit 'f363df8dbac6590b139a480303d1c3c3d69505ec' into cm-11.0-sgt7
Merge remote-tracking branch 'cm/cm-11.0' into cm-11.0-sgt7