efi_selftest: fix typos

fix typos
correct the header comment of efi_selftest_variables.c

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/lib/efi_selftest/efi_selftest_crc32.c b/lib/efi_selftest/efi_selftest_crc32.c
index 8555b8f..4881e8a 100644
--- a/lib/efi_selftest/efi_selftest_crc32.c
+++ b/lib/efi_selftest/efi_selftest_crc32.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2018 Heinrich Schuchardt <xypron.glpk@gmx.de>
  *
  * This unit test checks the CalculateCrc32 bootservice and checks the
- * headers of the system table, the boot services tablle, and the runtime
+ * headers of the system table, the boot services table, and the runtime
  * services table before and after ExitBootServices().
  */
 
@@ -19,7 +19,7 @@
 {
 	efi_status_t ret;
 	u32 crc32, res;
-	/* Casting from const to not const */
+	/* Casting from constant to not constant */
 	struct efi_table_hdr *hdr = (struct efi_table_hdr *)table;
 
 	if (!hdr->signature) {