i965/gen9: Set horizontal alignment for the miptree
i965/gen9: Set horizontal alignment for the miptree

v3: Use ffs() and a switch loop in
    tr_mode_vertical_texture_alignment() (Ben)

Signed-off-by: Anuj Phogat <e2026475996c48f0b97fd37e84129b3912980428@gmail.com>
Reviewed-by: Ben Widawsky <73675debcd8a436be48ec22211dcf44fe0df0a64@bwidawsk.net>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler