remove forced gcc optimization

It was added in 6d6bd8ba78434ecb09395582b5f3e41febd4d4ee,
but it is unclear for me, why this is needed or if it is
required. I don't think we should depend on some gcc
optimization, which might change in the future.
Anyway, this breaks c6x toolchain building (ICE), so I remove it.
Testsuite run for supported architectures didn't add any
new errors.

libc/unistd/daemon.c

@@ -69,7 +69,6 @@
 /* use clone() to get fork() like behavior here -- we just want to disassociate
  * from the controlling terminal
  */
-static inline attribute_optimize("O3")
 pid_t _fork_parent(void)
 {
 	INTERNAL_SYSCALL_DECL(err);