[9front] [patch] games/blit: Make 32-bit unsigned complement zero-extended to 64 bits explicit to silence compiler warning

[Alexander Kapshuk <alexander.kapshuk@gmail.com>]

Compilation outputs these warnings:

cpu% mk
6c -FTVw blit.c
6c -FTVw cpu.c
6c -FTVw mem.c
6c -FTVw telnet.c
warning: cpu.c:244 32-bit unsigned complement zero-extended to 64 bits
warning: cpu.c:255 32-bit unsigned complement zero-extended to 64 bits
warning: cpu.c:266 32-bit unsigned complement zero-extended to 64 bits
6l  -o 6.out blit.6 cpu.6 mem.6 telnet.6

Type cast one of the u32int variables involved in the expression to
u64int to make zero-extension explicit and silence compiler warning.

diff 0676a1ba51784e2b44ce9100965e4554e13e48b9 uncommitted
--- a/sys/src/games/blit/cpu.c
+++ b/sys/src/games/blit/cpu.c
@@ -241,7 +241,7 @@
  rS |= FLAGC;
  if((v & 0x80) != 0)
  rS |= FLAGN;
- if((~(w ^ u) & (v ^ u) & 0x80) != 0)
+ if((~((u64int)w ^ u) & (v ^ u) & 0x80) != 0)
  rS |= FLAGV;
  if((u8int)v != 0)
  rS &= ~FLAGZ;
@@ -252,7 +252,7 @@
  rS |= FLAGC;
  if((v & 0x8000) != 0)
  rS |= FLAGN;
- if((~(w ^ u) & (v ^ u) & 0x8000) != 0)
+ if((~((u64int)w ^ u) & (v ^ u) & 0x8000) != 0)
  rS |= FLAGV;
  if((u16int)v != 0)
  rS &= ~FLAGZ;
@@ -263,7 +263,7 @@
  rS |= FLAGC;
  if((v & 0x80000000) != 0)
  rS |= FLAGN;
- if((~(w ^ u) & (v ^ u) & 0x80000000) != 0)
+ if((~((u64int)w ^ u) & (v ^ u) & 0x80000000) != 0)
  rS |= FLAGV;
  if((u32int)v != 0)
  rS &= ~FLAGZ;