src/lib: Fix typos

Change-Id: Ia1da6637cfca5ddbd0879ea271bc68bb881b92e3
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37563
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/lib/b64_decode.c

@@ -97,7 +97,7 @@ size_t b64_decode(const uint8_t *input_data,
 	bd.data_size = input_length;
 	bd.input_index = 0;
 
-	while (1) { /* Until input is exausted. */
+	while (1) { /* Until input is exhausted. */
 		int v = get_next_char(&bd);
 
 		if (v < 0) {