std.zig.system: fix check for sparc "v8+" in getExternalExecutor()

Targeting v9 on sparc32 doesn't by itself imply "v8+" mode (64-bit instructions
in 32-bit code).
f96321be90Alex Rønne Petersen committed on 8/25/2025, 4:50:48 PMparenta51e88c
1 file changedLine totals unavailable