Partial revert of 413fc34b.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55421

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56244

It makes more sense to have it matching fx_5_0 format, which
uses the same flag for TBUFFER case, and also keeps 'single' modifier in there.
This modifier is ignored on fx_4_x, so it's only needed to be implemented
in the compiler.
Signed-off-by: Nikolay Sivov <nsivov@codeweavers.com>

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56279

Signed-off-by: Eric Pouech <epouech@codeweavers.com>

Signed-off-by: Eric Pouech <epouech@codeweavers.com>

Signed-off-by: Eric Pouech <epouech@codeweavers.com>

Signed-off-by: Eric Pouech <epouech@codeweavers.com>

Still fails spuriously from time to time as the IME sometimes doesn't
kick in, but hopefully less often.