mesa: don't enable NV_fragment_program_option with swrast

mesa: don't enable NV_fragment_program_option with swrast

Since dropping some NV_fragment_program opcodes (commits
868f95f1da74cf6dd7468cba1b56664aad585ccb, a3688d686f147f4252d19b298ae26d4ac72c2e08)
we can no longer parse all opcodes necessary for this extension, leading
to bugs (https://bugs.freedesktop.org/show_bug.cgi?id=86980).
Hence don't announce support for it in swrast (no other driver enabled it).
(Note that remnants of some NV_fp/vp extensions remain, they could be
dropped but are required as hacks for getting viewperf11 catia to run.)