hv: add functions to initialize vmsix capability

- add 'vpci_add_capability()' to initialize one
   PCI capability in config space.
 - add 'add_vmsix_capability()' to add vmsix capability.

Tracked-On: #5407
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Reviewed-by: Li, Fei <fei1.li@intel.com>
Reviewed-by: Wang, Yu1 <yu1.wang@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/include/lib/util.h

@@ -15,6 +15,9 @@
 /** Roundup (x/y) to ( x/y + (x%y) ? 1 : 0) **/
 #define INT_DIV_ROUNDUP(x, y)	((((x)+(y))-1)/(y))
 
+/** Roundup (x) to (y) aligned **/
+#define roundup(x, y)  (((x) + ((y) - 1UL)) & (~((y) - 1UL)))
+
 #define min(x, y)	((x) < (y)) ? (x) : (y)
 
 #define max(x, y)	((x) < (y)) ? (y) : (x)