ext/opcache/jit/zend_jit_trace: add missing lock for EXIT_INVALIDATE

Commit 6c25413 added the flag ZEND_JIT_EXIT_INVALIDATE which
resets the trace handlers in zend_jit_trace_exit(), but forgot to
lock the shared memory section.

This could cause another worker process who still saw the
ZEND_JIT_TRACE_JITED flag to schedule ZEND_JIT_TRACE_STOP_LINK, but
when it arrived at the ZEND_JIT_DEBUG_TRACE_STOP, the handler was
already reverted by the first worker process and thus
zend_jit_find_trace() fails.

This in turn generated a bogus jump offset in the JITed code, crashing
the PHP process.

Author: MaxKellermann

ext/opcache/jit/zend_jit_trace.c

@@ -8126,6 +8126,7 @@ int ZEND_FASTCALL zend_jit_trace_exit(uint32_t exit_num, zend_jit_registers_buf
 			t = &zend_jit_traces[num];
 		}
 
+		zend_shared_alloc_lock();
 		SHM_UNPROTECT();
 		zend_jit_unprotect();
 
@@ -8142,6 +8143,7 @@ int ZEND_FASTCALL zend_jit_trace_exit(uint32_t exit_num, zend_jit_registers_buf
 
 		zend_jit_protect();
 		SHM_PROTECT();
+		zend_shared_alloc_unlock();
 
 		return 0;
 	}