php: delete /usr/lib/php/build instead of /usr/lib/php

Fixes #8121

External PHP modules like the OPcache may live in
/usr/lib/php/extensions, so only delete /usr/lib/php/build

Signed-off-by: Floris Bos <bos@je-eigen-domein.nl>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/php/php.mk

@@ -295,7 +295,7 @@ endef
 PHP_POST_INSTALL_TARGET_HOOKS += PHP_EXTENSIONS_FIXUP
 
 define PHP_INSTALL_FIXUP
-	rm -rf $(TARGET_DIR)/usr/lib/php
+	rm -rf $(TARGET_DIR)/usr/lib/php/build
 	rm -f $(TARGET_DIR)/usr/bin/phpize
 	$(INSTALL) -D -m 0755 $(PHP_DIR)/php.ini-production \
 		$(TARGET_DIR)/etc/php.ini