fixup error when LINUX_BACKPORT macro was added

fixup error when LINUX_BACKPORT macro was added

Commit a05e783cb8853210628bd1f2bd82d17dd004c9d1 did not properly
backport the symbols for:

schedule_delayed_work
schedule_delayed_work_on

as it left the 'compat' string there when adding the LINUX_BACKPORT
symbol.  This resulted in these two not getting redefined and kernels
with these backported resulted in duplicate symbols when trying to load
compat.ko.

Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>