[package] opkg:

[package] opkg:
	- replace package list parser by something that works with fixed buffers
	  to avoid slurping the whole file into memory during parsing
	- fix a possible null pointer dereference in opkg_remove_cmd()
	- get rid of upgrade, it cannot upgrade single packages and kills
	  the system in most cases
	- get rid of the flag operation, not needed
	- bump package revision

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@18119 3c298f89-4303-0410-b956-a3cf2f4a3e73