Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/mm/sparse.c b/mm/sparse.c
index 9325020..aa64b12 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -500,7 +500,7 @@
 	 * so alloc 2M (with 2M align) and 24 bytes in turn will
 	 * make next 2M slip to one more 2M later.
 	 * then in big system, the memory will have a lot of holes...
-	 * here try to allocate 2M pages continously.
+	 * here try to allocate 2M pages continuously.
 	 *
 	 * powerpc need to call sparse_init_one_section right after each
 	 * sparse_early_mem_map_alloc, so allocate usemap_map at first.