Non-generic Arm flags

[jolting]

In OpenNI2/ThirdParty/PSCommon/BuildSystem/Platform.Arm this line should probably be removed.
CFLAGS += -march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp #-mcpu=cortex-a8

Not all arm systems are cortex-a9, armv7-a, support neon and most importantly some use hard float abis. These CFLAGS should be specified at compile time for a specific platform by passing them into make.

For example -mfloat-abi=softfp creates build errors on Ubuntu 14.04 armhf.

It seems that the neon is required. It should probably be noted somewhere that OpenNI2 only supports ARM with NEON.