av_mod_uintp2_c uses a bitwise AND with (1 << p) - 1 to clear the high
bits of an unsigned int. But this is undefined if p == 31, because 1 is
an int and 2^31 is not representable in an int. So make 1 unsigned.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>