egl: Additional attribute validation for eglCreatePbufferSurface

egl: Additional attribute validation for eglCreatePbufferSurface

eglCreatePbufferSurface should generate an EGL_BAD_MATCH error if:
1: The EGL_TEXTURE_FORMAT attribute is EGL_NO_TEXTURE and EGL_TEXTURE_TARGET
is something other than EGL_NO_TEXTURE
2: EGL_TEXTURE_FORMAT is something other than EGL_NO_TEXTURE and
EGL_TEXTURE_TARGET is EGL_NO_TEXTURE.

This fixes the dEQP-EGL.functional.negative_api.create_pbuffer_surface test.

Signed-off-by: Plamena Manolova <plamena.manolova@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>