Drivers: hv: Export some symbols for mshv_vtl

MSHV_VTL driver is going to be introduced, which is supposed to
provide interface for Virtual Machine Monitors (VMMs) to control
Virtual Trust Level (VTL). Export the symbols needed
to make it work (vmbus_isr, hv_context and hv_post_message).

Co-developed-by: Roman Kisel <[e-mail]>
Signed-off-by: Roman Kisel <[e-mail]>
Co-developed-by: Saurabh Sengar <[e-mail]>
Signed-off-by: Saurabh Sengar <[e-mail]>
Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Reviewed-by: Michael Kelley <[e-mail]>
Signed-off-by: Naman Jain <[e-mail]>
Signed-off-by: Wei Liu <[e-mail]>

drivers/hv/hv.c

···
 #include <linux/clockchips.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
+#include <linux/export.h>
 #include <clocksource/hyperv_timer.h>
 #include <asm/mshyperv.h>
 #include <linux/set_memory.h>
···
 
 /* The one and only */
 struct hv_context hv_context;
+EXPORT_SYMBOL_FOR_MODULES(hv_context, "mshv_vtl");
 
 /*
  * hv_init - Main initialization routine.
···
 
 	return hv_result(status);
 }
+EXPORT_SYMBOL_FOR_MODULES(hv_post_message, "mshv_vtl");
 
 static int hv_alloc_page(void **page, bool decrypt, const char *note)
 {

drivers/hv/hyperv_vmbus.h

···
  */
 #define HV_UTIL_NEGO_TIMEOUT 55
 
+void vmbus_isr(void);
 
 /* Definitions for the monitored notification facility */
 union hv_monitor_trigger_group {

drivers/hv/vmbus_drv.c

···
 #include <linux/syscore_ops.h>
 #include <linux/dma-map-ops.h>
 #include <linux/pci.h>
+#include <linux/export.h>
 #include <clocksource/hyperv_timer.h>
 #include <asm/mshyperv.h>
 #include "hyperv_vmbus.h"
···
 	}
 }
 
-static void vmbus_isr(void)
+void vmbus_isr(void)
 {
 	struct hv_per_cpu_context *hv_cpu
 		= this_cpu_ptr(hv_context.cpu_context);
···
 
 	add_interrupt_randomness(vmbus_interrupt);
 }
+EXPORT_SYMBOL_FOR_MODULES(vmbus_isr, "mshv_vtl");
 
 static irqreturn_t vmbus_percpu_isr(int irq, void *dev_id)
 {