x86: cabac: allow building with suncc

This fixes two issues preventing suncc from building this code.

The undocumented 'a' operand modifier, causing gcc to omit a $ in
front of immediate operands (as required in addresses), is not
supported by suncc.  Luckily, the also undocumented 'c' modifer
has the same effect and is supported.

On some asm statements with a large number of operands, suncc for no
obvious reason fails to correctly substitute some of the operands.
Fortunately, some of the operands in these statements are plain
numbers which can be inserted directly into the code block instead
of passed as operands.

With these changes, the code builds correctly with both gcc and
suncc.

Signed-off-by: Mans Rullgard <mans@mansr.com>
