Remove useless code in InjectionPointAttach()

strlcpy() ensures that a target string is zero-terminated, so there is
no need to enforce it a second time in this code.  This simplification
could have been done in 0eb23285a2.

Author: Feilong Meng <feelingmeng@foxmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/tencent_771178777C5BC17FCB7F7A1771CD1FFD5708@qq.com

src/backend/utils/misc/injection_point.c

@@ -331,11 +331,8 @@ InjectionPointAttach(const char *name,
 
 	/* Save the entry */
 	strlcpy(entry->name, name, sizeof(entry->name));
-	entry->name[INJ_NAME_MAXLEN - 1] = '\0';
 	strlcpy(entry->library, library, sizeof(entry->library));
-	entry->library[INJ_LIB_MAXLEN - 1] = '\0';
 	strlcpy(entry->function, function, sizeof(entry->function));
-	entry->function[INJ_FUNC_MAXLEN - 1] = '\0';
 	if (private_data != NULL)
 		memcpy(entry->private_data, private_data, private_data_size);