arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSE

commit d4022a335271a48cce49df35d825897914fbffe3 upstream.

Update wall-to-monotonic fields in the VDSO data page
unconditionally.  These are used to service CLOCK_MONOTONIC_COARSE,
which is not guarded by use_syscall.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>