build: Remove --enable-gprof

This build option has been deprecated since 8.0.
Remove all CONFIG_GPROF code that depends on that,
including one errant check using TARGET_GPROF.

Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

bsd-user/bsd-proc.h

@@ -25,9 +25,6 @@
 /* exit(2) */
 static inline abi_long do_bsd_exit(void *cpu_env, abi_long arg1)
 {
-#ifdef TARGET_GPROF
-    _mcleanup();
-#endif
     gdb_exit(arg1);
     qemu_plugin_user_exit();
     _exit(arg1);