[PATCH] x86/mem_sharing: Fix build folloing VM Fork work

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

A default build fails with:

  mem_sharing.c: In function ‘copy_special_pages’:
  mem_sharing.c:1649:9: error: ‘HVM_PARAM_STORE_PFN’ undeclared (first use in 
this function)
           HVM_PARAM_STORE_PFN,
           ^~~~~~~~~~~~~~~~~~~

I suspect this is a rebasing issue with respect to c/s 12f0c69f2709 "x86/HVM:
reduce hvm.h include dependencies".

Fixes: 41548c5472a "mem_sharing: VM forking"
Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Tamas K Lengyel <tamas@xxxxxxxxxxxxx>
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Wei Liu <wl@xxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
 xen/arch/x86/mm/mem_sharing.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index 85951b7bea..e572e9e39d 100644
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -41,6 +41,8 @@
 #include <asm/hvm/hvm.h>
 #include <xsm/xsm.h>
 
+#include <public/hvm/params.h>
+
 #include "mm-locks.h"
 
 static shr_handle_t next_handle = 1;
-- 
2.11.0