Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
index 99aa0e5..26cd9d1 100644
--- a/drivers/scsi/imm.c
+++ b/drivers/scsi/imm.c
@@ -3,7 +3,7 @@
  * 
  * (The IMM is the embedded controller in the ZIP Plus drive.)
  * 
- * My unoffical company acronym list is 21 pages long:
+ * My unofficial company acronym list is 21 pages long:
  *      FLA:    Four letter acronym with built in facility for
  *              future expansion to five letters.
  */