Align the declarations of BIT_readBits() and BIT_reloadDStream() in
bitstream.h with their FORCE_INLINE_TEMPLATE definitions.
The previous MEM_STATIC declarations caused an attribute mismatch
between the header and the definitions, which can lead to incorrect
compiler assumptions under certain toolchains and optimization levels.
Signed-off-by: Alexander Moch <mail@alexmoch.com>