virt: detect the ACRN hypervisor

Add magic string and enumeration for the ACRN hypervisor
(https://projectacrn.org).

src/basic/virt.c

@@ -40,6 +40,8 @@ static int detect_vm_cpuid(void) {
                 /* https://wiki.freebsd.org/bhyve */
                 { "bhyve bhyve ", VIRTUALIZATION_BHYVE     },
                 { "QNXQVMBSQG",   VIRTUALIZATION_QNX       },
+                /* https://projectacrn.org */
+                { "ACRNACRNACRN", VIRTUALIZATION_ACRN      },
         };
 
         uint32_t eax, ebx, ecx, edx;
@@ -628,6 +630,7 @@ static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
         [VIRTUALIZATION_PARALLELS] = "parallels",
         [VIRTUALIZATION_BHYVE] = "bhyve",
         [VIRTUALIZATION_QNX] = "qnx",
+        [VIRTUALIZATION_ACRN] = "acrn",
         [VIRTUALIZATION_VM_OTHER] = "vm-other",
 
         [VIRTUALIZATION_SYSTEMD_NSPAWN] = "systemd-nspawn",

src/basic/virt.h

@@ -21,6 +21,7 @@ enum {
         VIRTUALIZATION_PARALLELS,
         VIRTUALIZATION_BHYVE,
         VIRTUALIZATION_QNX,
+        VIRTUALIZATION_ACRN,
         VIRTUALIZATION_VM_OTHER,
         VIRTUALIZATION_VM_LAST = VIRTUALIZATION_VM_OTHER,