Fix misspellings using 'codespell' tool

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fio.1 b/fio.1
index b8082af..07e4a62 100644
--- a/fio.1
+++ b/fio.1
@@ -353,7 +353,7 @@
 Specify a range of I/O block sizes.  The issued I/O unit will always be a
 multiple of the minimum size, unless \fBblocksize_unaligned\fR is set.  Applies
 to both reads and writes if only one range is given, but can be specified
-separately with a comma seperating the values. Example: bsrange=1k-4k,2k-8k.
+separately with a comma separating the values. Example: bsrange=1k-4k,2k-8k.
 Also (see \fBblocksize\fR).
 .TP
 .BI bssplit \fR=\fPstr
@@ -738,12 +738,12 @@
 .BI rate_iops \fR=\fPint
 Cap the bandwidth to this number of IOPS. Basically the same as rate, just
 specified independently of bandwidth. The same format as \fBrate\fR is used for
-read vs write seperation. If \fBblocksize\fR is a range, the smallest block
+read vs write separation. If \fBblocksize\fR is a range, the smallest block
 size is used as the metric.
 .TP
 .BI rate_iops_min \fR=\fPint
 If this rate of I/O is not met, the job will exit. The same format as \fBrate\fR
-is used for read vs write seperation.
+is used for read vs write separation.
 .TP
 .BI ratecycle \fR=\fPint
 Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of