Fix typos.

Typos found with codespell.

Please keep in mind that this should have impact on actual code
and must be carefully evaluated:

src/core/or/lttng_circuit.inc
-    ctf_enum_value("CONTROLER", CIRCUIT_PURPOSE_CONTROLLER)
+    ctf_enum_value("CONTROLLER", CIRCUIT_PURPOSE_CONTROLLER)

src/lib/encoding/binascii.c

@@ -275,7 +275,7 @@ base64_encode(char *dest, size_t destlen, const char *src, size_t srclen,
   }
   switch (n_idx) {
   case 0:
-    /* 0 leftover bits, no pading to add. */
+    /* 0 leftover bits, no padding to add. */
     break;
   case 1:
     /* 8 leftover bits, pad to 12 bits, write the 2 6-bit values followed