meson: Fix typo that breaks -Dgalium-xvmc=false

_xmvc -> _xvmc. Sigh

Fixes: a6943bb4ce99ea7af7222552f1326fb80823d0b2
       ("meson: Fix auto option for xvmc")
Signed-off-by: Dylan Baker <dylan.c.baker@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Tested-by: Clayton Craft <clayton.a.craft@intel.com>
1 file changed