This patch adds 2 missing symbol exports: jiffies_to_timeval() and
timeval_to_jiffies(). The (not yet merged) dm-raid4-5 module will need
them, and they used to be indirectly exported by virtue of being inline
functions.
Commit 8b9365d753d9870bb6451504c13570b81923228f ("[PATCH] Uninline
jiffies.h functions") uninlined them, and thus modules now need them
explicitly exported to use them.