vdso.7: Update CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE info for powerpc
See https://bugzilla.kernel.org/show_bug.cgi?id=213419
ppc/32 and ppc/64 sections both have the following note:
The CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE clocks are
not supported by the __kernel_clock_getres and
__kernel_clock_gettime interfaces; the kernel falls back to the
real system call
This note has been wrong from quite some time now, since commit
654abc69ef2e ("powerpc/vdso32: Add support for
CLOCK_{REALTIME/MONOTONIC}_COARSE") and commit
5c929885f1bb ("powerpc/vdso64: Add support for
CLOCK_{REALTIME/MONOTONIC}_COARSE")
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>