package/bayer2rgb-neon: new package

package/bayer2rgb-neon: new package

bayer2rgb-neon[1] is a library which allows decoding raw camera bayer
to RGB using NEON hardware acceleration.

[1]: https://git.phytec.de/bayer2rgb-neon/

Signed-off-by: Eloi Bail <eloi.bail@savoirfairelinux.com>
[Thomas:
 - use "config" instead of "menuconfig"
 - use BR2_ARM_CPU_HAS_NEON instead of BR2_ARM_ENABLE_NEON
 - use BR2_INSTALL_LIBSTDCPP instead of BR2_TOOLCHAIN_BUILDROOT_CXX
 - add dependency on BR2_TOOLCHAIN_GCC_AT_LEAST_4_9, because the code
   is using C++11
 - add missing Config.in comment
 - drop --prefix=/usr from CONF_OPTS, it is passed by the
   autotools-package infrastructure
 - simplify CFLAGS logic
 - move from "Applications" to "Libraries" in menuconfig
 - add missing .hash file
 - add entry in DEVELOPERS file]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>