config: remove PKG_PROG_PKG_CONFIG test If pkg-config is missing, the configuration fails while initializing XORG_* macros: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd line 11622: PKG_PROG_PKG_CONFIG: command not found The output is sufficient to locate the problem. It is not possible, or very difficult, to not have pkg-config installed as the whole desktop and countless other software depends on it. Acked-by: Daniel Stone <daniel@fooishbar.org> Reviewed-by: Kristian Høgsberg <krh@bitplanet.net> Signed-off-by: Gaetan Nadon <memsize@videotron.ca>