package/pkg-luarocks: drop flock at installation time

In commit 22b327fc74 ("pkg-luarocks: fix
top-level parallel makefile support"), a flock on $(TARGET_DIR) was
added to ensure that two Luarocks packages are not installed at the
same time.

However, to support top-level parallel build, we have now clearly
decided that per-package folders is a requirement. Therefore,
TARGET_DIR is anyway going to be different for each package, making
this flock unnecessary.

Trying to use top-level parallel build without per-package folder is
simply not supported, so this commit drops the unnecessary flock.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Acked-by: Francois Perrad <francois.perrad@gadz.org>

package/pkg-luarocks.mk

@@ -63,7 +63,7 @@ endif
 #
 ifndef $(2)_INSTALL_TARGET_CMDS
 define $(2)_INSTALL_TARGET_CMDS
-	cd $$($(2)_SRCDIR) && $$(LUAROCKS_RUN_ENV) flock $$(TARGET_DIR) \
+	cd $$($(2)_SRCDIR) && $$(LUAROCKS_RUN_ENV) \
 		$$(LUAROCKS_RUN_CMD) make --keep $$($(2)_ROCKSPEC) $$($(2)_BUILD_OPTS)
 endef
 endif