tests: Re-enable 'Hello World' 32-bit tests

Due to a faul recorded here:
https://gem5.atlassian.net/browse/GEM5-1074, running 32-bit binaries in
SE mode was causing a segfault to occur. These tests were therefore
disabled until a fix could be developed. A fix was submitted here:
https://gem5-review.googlesource.com/c/public/gem5/+/51489, and, as-such
the tests should be re-enabled.

Change-Id: Id01a6d85fb5e30319e53dda97f6247bcc5302477
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/51612
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

tests/gem5/hello_se/test_hello_se.py

@@ -49,13 +49,11 @@ import re
 static_progs = {
     constants.gcn3_x86_tag: (
         "x86-hello64-static",
-        # "x86-hello32-static", # Running 32-bit binaries on gem5 is broken:
-                                # https://gem5.atlassian.net/browse/GEM5-1074
+        "x86-hello32-static",
     ),
     constants.arm_tag: (
         "arm-hello64-static",
-        # "arm-hello32-static", # Running 32-bit binaries on gem5 is broken.
-                                # https://gem5.atlassian.net/browse/GEM5-1074
+        "arm-hello32-static",
     ),
     constants.mips_tag: ("mips-hello",),
     constants.riscv_tag: ("riscv-hello",),