Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 801dd08..7ebeed0 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2267,7 +2267,7 @@
  * of bytes already consumed and the next call to
  * skb_seq_read() will return the remaining part of the block.
  *
- * Note 1: The size of each block of data returned can be arbitary,
+ * Note 1: The size of each block of data returned can be arbitrary,
  *       this limitation is the cost for zerocopy seqeuental
  *       reads of potentially non linear data.
  *