uboot-imx

fs: fat: Drop CONFIG_SUPPORT_VFAT

fat.h unconditionally defines CONFIG_SUPPORT_VFAT (and has done since
2003), so as a result VFAT support is always enabled regardless of
whether a board config defines it or not. Drop this unnecessary option.

Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>