egl/android: Only keep BGRA EGL configs as fallback

Stock Android code actually doesn't support BGRA format EGL
configs. It's hard coded to use RGBA_8888 as window format
for BGRA EGL configs here:
https://android.googlesource.com/platform/frameworks/native/+/1eb32e2/opengl/libs/EGL/eglApi.cpp#608
So just remove it from EGL configs if RGBA is supported.

Signed-off-by: Lepton Wu <lepton@chromium.org>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
22 jobs for !1865 with nobgra in 15 minutes and 30 seconds (queued for 3 seconds)
merge request