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_unaligned.c b/lib/efi_selftest/efi_selftest_unaligned.c
index 1802948..6fce110 100644
--- a/lib/efi_selftest/efi_selftest_unaligned.c
+++ b/lib/efi_selftest/efi_selftest_unaligned.c
@@ -19,7 +19,7 @@
  * occurs.
  *
  * @addr:	address to read
- * @return:	value at the address
+ * Return:	value at the address
  */
 static inline u32 deref(u32 *addr)
 {
@@ -37,7 +37,7 @@
  * Execute unit test.
  * An unaligned memory access is executed. The result is checked.
  *
- * @return:	EFI_ST_SUCCESS for success
+ * Return:	EFI_ST_SUCCESS for success
  */
 static int execute(void)
 {