x86/hvm: address violations of Rule 20.7

MISRA C Rule 20.7 states: "Expressions resulting from the expansion
of macro parameters shall be enclosed in parentheses". Therefore, some
macro definitions should either gain additional parentheses or have
their expressions simplified to ensure that all current and future users
will be safe with respect to expansions that can possibly alter the
semantics of the passed-in macro parameter.

No functional change.

Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/hvm/hvm.c

@@ -1066,9 +1066,9 @@ static int cf_check hvm_load_cpu_ctxt(struct domain *d, hvm_domain_context_t *h)
     /* Older Xen versions used to save the segment arbytes directly 
      * from the VMCS on Intel hosts.  Detect this and rearrange them
      * into the struct segment_register format. */
-#define UNFOLD_ARBYTES(_r)                          \
-    if ( (_r & 0xf000) && !(_r & 0x0f00) )          \
-        _r = ((_r & 0xff) | ((_r >> 4) & 0xf00))
+#define UNFOLD_ARBYTES(_r)                              \
+    if ( ((_r) & 0xf000) && !((_r) & 0x0f00) )          \
+        (_r) = (((_r) & 0xff) | (((_r) >> 4) & 0xf00))
     UNFOLD_ARBYTES(ctxt.cs_arbytes);
     UNFOLD_ARBYTES(ctxt.ds_arbytes);
     UNFOLD_ARBYTES(ctxt.es_arbytes);

xen/arch/x86/include/asm/hvm/save.h

@@ -128,9 +128,9 @@ static int __init cf_check __hvm_register_##_x##_save_and_restore(void)   \
 {                                                                         \
     hvm_register_savevm(HVM_SAVE_CODE(_x),                                \
                         #_x,                                              \
-                        &_save,                                           \
+                        _save,                                            \
                         check,                                            \
-                        &_load,                                           \
+                        _load,                                            \
                         (_num) * (HVM_SAVE_LENGTH(_x)                     \
                                   + sizeof (struct hvm_save_descriptor)), \
                         _k);                                              \