vrend: guard minigbm usage bit in vrend_fromat_can_sample()
GBM_BO_USE_TEXTURING is available in minigbm's gbm.h but not in mesa's gbm.h. Texture usage is implied with usage 0 in mesa gbm.
GBM_BO_USE_TEXTURING is available in minigbm's gbm.h but not in mesa's gbm.h. Texture usage is implied with usage 0 in mesa gbm.