Drivers: hv vmbus: Move Hypercall page setup out of common code

As part of the effort to separate out architecture specific code, move the
hypercall page setup to an architecture specific file.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 15a0c27..e5f57e1 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -80,4 +80,9 @@ void hv_setup_kexec_handler(void (*handler)(void));
 void hv_remove_kexec_handler(void);
 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
 void hv_remove_crash_handler(void);
+
+#if IS_ENABLED(CONFIG_HYPERV)
+void hyperv_init(void);
+extern void *hv_hypercall_pg;
+#endif
 #endif