x86/hyperv: Move hv_do_rep_hypercall to asm-generic

This patch makes no functional changes.  It simply moves hv_do_rep_hypercall()
out of arch/x86/include/asm/mshyperv.h and into asm-generic/mshyperv.h

hv_do_rep_hypercall() is architecture independent, so it makes sense that it
should be in the architecture independent mshyperv.h, not in the x86-specific
mshyperv.h.

This is done in preperation for a follow up patch which creates a consistent
pattern for checking Hyper-V hypercall status.

Signed-off-by: Joseph Salisbury <joseph.salisbury@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1618620183-9967-1-git-send-email-joseph.salisbury@linux.microsoft.com


Signed-off-by: Wei Liu <wei.liu@kernel.org>