Arm/guestcopy: avoid use of "current" in compound literals

Compound literals are also covered by Misra C:2012 rule 13.1
("Initializer lists shall not contain persistent side effects"), and
(sadly?) that rule also applies to lists with just a single element, or
more generally with just a single side effect. Use intermediate variables
to overcome this.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>

xen/arch/arm/guestcopy.c

@@ -109,29 +109,37 @@ static unsigned long copy_guest(void *buf, uint64_t addr, unsigned long len,
 
 unsigned long raw_copy_to_guest(void *to, const void *from, unsigned int len)
 {
+    struct vcpu *curr = current;
+
     return copy_guest((void *)from, /* COPY_to_guest doesn't modify */
-                      (vaddr_t)to, len, GVA_INFO(current),
+                      (vaddr_t)to, len, GVA_INFO(curr),
                       COPY_to_guest | COPY_linear);
 }
 
 unsigned long raw_copy_to_guest_flush_dcache(void *to, const void *from,
                                              unsigned int len)
 {
+    struct vcpu *curr = current;
+
     return copy_guest((void *)from, /* COPY_to_guest doesn't modify */
-                      (vaddr_t)to, len, GVA_INFO(current),
+                      (vaddr_t)to, len, GVA_INFO(curr),
                       COPY_to_guest | COPY_flush_dcache | COPY_linear);
 }
 
 unsigned long raw_clear_guest(void *to, unsigned int len)
 {
-    return copy_guest(NULL, (vaddr_t)to, len, GVA_INFO(current),
+    struct vcpu *curr = current;
+
+    return copy_guest(NULL, (vaddr_t)to, len, GVA_INFO(curr),
                       COPY_to_guest | COPY_linear);
 }
 
 unsigned long raw_copy_from_guest(void *to, const void __user *from,
                                   unsigned int len)
 {
-    return copy_guest(to, (vaddr_t)from, len, GVA_INFO(current),
+    struct vcpu *curr = current;
+
+    return copy_guest(to, (vaddr_t)from, len, GVA_INFO(curr),
                       COPY_from_guest | COPY_linear);
 }