hv:remove some unnecessary includes

--remove unnecessary includes
--remove unnecssary forward-declaration for 'struct vhm_request'

Tracked-On: #861
Signed-off-by: Mingqiang Chi <mingqiang.chi@intel.com>

hypervisor/common/hv_main.c

@@ -10,7 +10,6 @@
 #include <vmexit.h>
 #include <irq.h>
 #include <schedule.h>
-#include <softirq.h>
 #include <profiling.h>
 #include <trace.h>
 #include <logmsg.h>

hypervisor/common/vm_load.c

@@ -7,7 +7,6 @@
 #include <vm.h>
 #include <e820.h>
 #include <zeropage.h>
-#include <boot_context.h>
 #include <ept.h>
 #include <mmu.h>
 #include <multiboot.h>