package/avrdude: remove the obsolete hook

Since its introduction in commit [1], avrdude has a post install
target hook removing a backup configuration file.

Commit [2] updated avrdude to version 7.1 and switch to the
cmake infra.

CMake recipe doesn't create a backup of the avrdude.conf.

This commit removes this hook which is no longer needed.

[1] https://gitlab.com/buildroot.org/buildroot/-/commit/dc776f0d0546900b22d1552f3e522be2080016c6
[2] https://gitlab.com/buildroot.org/buildroot/-/commit/f89f3787a05d123a33f1a000c802fe42c96a487f

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
[Julien: add extra info in commit log]
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/avrdude/avrdude.mk

@@ -29,12 +29,4 @@ ifeq ($(BR2_PACKAGE_HIDAPI),y)
 AVRDUDE_DEPENDENCIES += hidapi
 endif
 
-# if /etc/avrdude.conf exists, the installation process creates a
-# backup file, which we do not want in the context of Buildroot.
-define AVRDUDE_REMOVE_BACKUP_FILE
-	$(RM) -f $(TARGET_DIR)/etc/avrdude.conf.bak
-endef
-
-AVRDUDE_POST_INSTALL_TARGET_HOOKS += AVRDUDE_REMOVE_BACKUP_FILE
-
 $(eval $(cmake-package))