DEVELOPERS: remove Bernd Kuhls from libglfw

I am not using this package anymore.

Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

DEVELOPERS

@@ -418,7 +418,6 @@ F:	package/libfreeglut/
 F:	package/libfribidi/
 F:	package/libg7221/
 F:	package/libglew/
-F:	package/libglfw/
 F:	package/libglu/
 F:	package/libhdhomerun/
 F:	package/libheif/