lx_config.sh: fix typo: $$ROCKCFG_PKG_LINUX_CONFIG_STYLE
lx_config.sh: make an oldconfig when config style = none
to fillout any comments stripped from linux.cfg and add
any new comments/settings if the target kernel is newer
than the one used to create linux.cfg (make xconfig and
menuconfig seem to need the comments from some purpose).
linux24-src.conf: don't copy .config_{nomods,modules} if
config style = none (they don't exist in this case).
git-svn-id: http://www.rocklinux.org/svn/rock-linux/trunk@1366 c5f82cb5-29bc-0310-9cd0-bff59a50e3bc