Fix: remove unused variables

[amalchuk]

When make is processing, I've got a warnings such as:

src/g_newai.c:424:6: warning: variable 'count1' set but not used [-Wunused-but-set-variable]
  424 |         int count1 = 0, count2 = 0, count4 = 0, count5 = 0;
      |             ^
src/g_newai.c:424:18: warning: variable 'count2' set but not used [-Wunused-but-set-variable]
  424 |         int count1 = 0, count2 = 0, count4 = 0, count5 = 0;
      |                         ^
src/g_newai.c:424:30: warning: variable 'count4' set but not used [-Wunused-but-set-variable]
  424 |         int count1 = 0, count2 = 0, count4 = 0, count5 = 0;
      |                                     ^
src/g_newai.c:918:16: warning: variable 'count2' set but not used [-Wunused-but-set-variable]
  918 |         int field, i, count2;
      |                       ^
src/g_spawn.c:307:9: warning: variable 'c2' set but not used [-Wunused-but-set-variable]
  307 |         int c, c2;
      |                ^

I have removed these unused variables. Tested on macOS 15, it just works fine.

[Yamagi]

Thank you!