gpu-viv-bin-mx6q: fix compiling issues with EGL_API_FB

To compile with Vivante header and use framebuffer, it is necessary to
pass option -DEGL_API_FB. This option is declared in pkg-config file of
Vivante library. But many packages (especialy qt5 components) does not
consider these flags.

So instead of patching every packages that use EGL, it is more
convenient to patch Vivante headers.

This commit add #define EGL_API_FB on top of eglvivante.h when
necessary.

[Thomas: fix syntax error.]

Signed-off-by: Jérôme Pouiller <jezz@sysmic.org>
Tested-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>