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/arm/powertec.c b/drivers/scsi/arm/powertec.c
index e2297b4..9274c06 100644
--- a/drivers/scsi/arm/powertec.c
+++ b/drivers/scsi/arm/powertec.c
@@ -232,7 +232,7 @@
  * Params   : buffer  - a buffer to write information to
  *	      start   - a pointer into this buffer set by this routine to the start
  *		        of the required information.
- *	      offset  - offset into information that we have read upto.
+ *	      offset  - offset into information that we have read up to.
  *	      length  - length of buffer
  *	      inout   - 0 for reading, 1 for writing.
  * Returns  : length of data written to buffer.