efi: move efi_status_to_err() to efi.h

Move efi_status_to_err() into the efi.h header as it's generally useful
in all bits of EFI code where there is a need to convert an efi_status_t
to a kernel error value.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 391c67b..08b10a6 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -237,39 +237,6 @@
 	return fops->query_variable_store(attributes, size);
 }
 
-static int efi_status_to_err(efi_status_t status)
-{
-	int err;
-
-	switch (status) {
-	case EFI_SUCCESS:
-		err = 0;
-		break;
-	case EFI_INVALID_PARAMETER:
-		err = -EINVAL;
-		break;
-	case EFI_OUT_OF_RESOURCES:
-		err = -ENOSPC;
-		break;
-	case EFI_DEVICE_ERROR:
-		err = -EIO;
-		break;
-	case EFI_WRITE_PROTECTED:
-		err = -EROFS;
-		break;
-	case EFI_SECURITY_VIOLATION:
-		err = -EACCES;
-		break;
-	case EFI_NOT_FOUND:
-		err = -ENOENT;
-		break;
-	default:
-		err = -EINVAL;
-	}
-
-	return err;
-}
-
 static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor,
 				struct list_head *head)
 {
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 5d2a8b9..149f653 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -733,6 +733,39 @@
 	*addr &= PAGE_MASK;
 }
 
+static inline int efi_status_to_err(efi_status_t status)
+{
+	int err;
+
+	switch (status) {
+	case EFI_SUCCESS:
+		err = 0;
+		break;
+	case EFI_INVALID_PARAMETER:
+		err = -EINVAL;
+		break;
+	case EFI_OUT_OF_RESOURCES:
+		err = -ENOSPC;
+		break;
+	case EFI_DEVICE_ERROR:
+		err = -EIO;
+		break;
+	case EFI_WRITE_PROTECTED:
+		err = -EROFS;
+		break;
+	case EFI_SECURITY_VIOLATION:
+		err = -EACCES;
+		break;
+	case EFI_NOT_FOUND:
+		err = -ENOENT;
+		break;
+	default:
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
 /*
  * EFI Variable support.
  *