Updating Linux driver to use defined VM ID offset

The driver currently assumes VM IDs start at zero.  They start at 1, which is
defined by HF_VM_ID_OFFSET.

Bug: 132421503
Change-Id: I2e4a63f1aabc3ffab9621df85cbc49c658cc1b92
diff --git a/main.c b/main.c
index b2e787a..9b55798 100644
--- a/main.c
+++ b/main.c
@@ -42,7 +42,7 @@
 #define CONFIG_HAFNIUM_MAX_VMS   16
 #define CONFIG_HAFNIUM_MAX_VCPUS 32
 
-#define FIRST_SECONDARY_VM_ID 1
+#define FIRST_SECONDARY_VM_ID (HF_VM_ID_OFFSET + 1)
 
 struct hf_vcpu {
 	struct hf_vm *vm;
@@ -792,7 +792,7 @@
  */
 static void hf_free_resources(void)
 {
-	spci_vm_id_t i;
+	uint16_t i;
 	spci_vcpu_index_t j;
 
 	/*