Remove useless casting in asm "m" operand.

Patch by Matthieu Castet, castet D matthieu A free D fr

Originally committed as revision 18054 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/x86/snowdsp_mmx.c

@@ -667,7 +667,7 @@ void ff_snow_vertical_compose97i_mmx(IDWTELEM *b0, IDWTELEM *b1, IDWTELEM *b2, I
              "jnz 1b                         \n\t"\
              :"+m"(dst8),"+m"(dst_array),"=&r"(tmp)\
              :\
-             "rm"((x86_reg)(src_x<<1)),"m"(obmc),"a"(block),"m"((x86_reg)b_h),"m"((x86_reg)src_stride):\
+             "rm"((x86_reg)(src_x<<1)),"m"(obmc),"a"(block),"m"(b_h),"m"(src_stride):\
              "%"REG_c"","%"REG_S"","%"REG_D"","%"REG_d"");
 
 #define snow_inner_add_yblock_sse2_end_8\
@@ -815,7 +815,7 @@ snow_inner_add_yblock_sse2_end_16
              "jnz 1b                         \n\t"\
              :"+m"(dst8),"+m"(dst_array),"=&r"(tmp)\
              :\
-             "rm"((x86_reg)(src_x<<1)),"m"(obmc),"a"(block),"m"((x86_reg)b_h),"m"((x86_reg)src_stride):\
+             "rm"((x86_reg)(src_x<<1)),"m"(obmc),"a"(block),"m"(b_h),"m"(src_stride):\
              "%"REG_c"","%"REG_S"","%"REG_D"","%"REG_d"");
 
 static void inner_add_yblock_bw_8_obmc_16_mmx(const uint8_t *obmc, const x86_reg obmc_stride, uint8_t * * block, int b_w, x86_reg b_h,