powerpc/time: Move timebase functions into new asm/vdso/timebase.h

In order to easily use get_tb() from C VDSO, move timebase
functions into a new header named asm/vdso/timebase.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201126131006.2431205-3-mpe@ellerman.id.au
This commit is contained in:
Christophe Leroy 2020-11-27 00:10:00 +11:00 • committed by Michael Ellerman
commit d26b3817d9
4 changed files with 73 additions and 61 deletions