bsd-user/main.c: Drop syscall flavor arg -bsd

We've not realistically been able to actually run any bsd program on any
other bsd program. They are too diverged to do this easily. The current
code is setup to do it, but implementing it is hard. Stop pretending
that we can do this.

Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

bsd-user/main.c

@@ -164,7 +164,6 @@ static void usage(void)
            "-E var=value      sets/modifies targets environment variable(s)\n"
            "-U var            unsets targets environment variable(s)\n"
            "-B address        set guest_base address to address\n"
-           "-bsd type         select emulated BSD type FreeBSD/NetBSD/OpenBSD (default)\n"
            "\n"
            "Debug options:\n"
            "-d item1[,...]    enable logging of specified items\n"
@@ -392,17 +391,6 @@ int main(int argc, char **argv)
             have_guest_base = true;
         } else if (!strcmp(r, "drop-ld-preload")) {
             (void) envlist_unsetenv(envlist, "LD_PRELOAD");
-        } else if (!strcmp(r, "bsd")) {
-            if (!strcasecmp(argv[optind], "freebsd")) {
-                bsd_type = target_freebsd;
-            } else if (!strcasecmp(argv[optind], "netbsd")) {
-                bsd_type = target_netbsd;
-            } else if (!strcasecmp(argv[optind], "openbsd")) {
-                bsd_type = target_openbsd;
-            } else {
-                usage();
-            }
-            optind++;
         } else if (!strcmp(r, "seed")) {
             seed_optarg = optarg;
         } else if (!strcmp(r, "singlestep")) {