efi_loader: correct function comment style

Replace @return and @param.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_selftest/efi_selftest_esrt.c b/lib/efi_selftest/efi_selftest_esrt.c
index 99793de..922ff25 100644
--- a/lib/efi_selftest/efi_selftest_esrt.c
+++ b/lib/efi_selftest/efi_selftest_esrt.c
@@ -108,7 +108,7 @@
  * @esrt: pointer to the ESRT
  * @img_info: an image_info_descriptor output by the FMP get_image_info
  *
- * @return: true if matching ESRT entry is found and if all the ESRT entry fields match the
+ * Return: true if matching ESRT entry is found and if all the ESRT entry fields match the
  * corresponding @img_info fields.
  */
 static bool lib_test_check_uuid_entry(struct efi_system_resource_table *esrt,
@@ -168,7 +168,7 @@
  *
  * @handle:	handle of the loaded image
  * @systable:	system table
- * @return:	EFI_ST_SUCCESS for success
+ * Return:	EFI_ST_SUCCESS for success
  */
 static int setup(const efi_handle_t handle,
 		 const struct efi_system_table *systable)
@@ -185,7 +185,7 @@
  *
  * Uninstall the test FMP.
  *
- * @return:	EFI_ST_SUCCESS for success
+ * Return:	EFI_ST_SUCCESS for success
  */
 static int teardown(void)
 {