Snippets for aha 0.5.1 from FreeBSD 151arm64

Sourced from https://pkg-status.freebsd.org/ampere5/data/latest-per-pkg/aha/0.5.1_1/151arm64-default.log.

• aha.c:1146:35: warning: unknown warning group '-Wimplicit-fallthrough=', ignored [-Wunknown-warning-option]
   1146 |                         #pragma GCC diagnostic ignored "-Wimplicit-fallthrough="
        |                                                        ^
  

• aha.c:691:6: warning: variable 'momline' set but not used [-Wunused-but-set-variable]
    691 |         int momline=0;
        |             ^