Merge pull request #5527 from shawnanastasio/ppc64le

Implement support for powerpc64{,le}

Author: andrewrk

lib/std/os/bits/linux.zig

@@ -20,6 +20,7 @@ pub usingnamespace switch (builtin.arch) {
     .arm => @import("linux/arm-eabi.zig"),
     .riscv64 => @import("linux/riscv64.zig"),
     .mips, .mipsel => @import("linux/mips.zig"),
+    .powerpc64, .powerpc64le => @import("linux/powerpc64.zig"),
     else => struct {},
 };