powerpc/vdso: Remove unused clockmode asm offsets

These offsets are not used anymore, delete them.

Fixes: c39b1dcf ("powerpc/vdso: Add a page for non-time data")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241113-vdso-powerpc-asm-offsets-v1-1-3f7e589f090d@linutronix.de