doc: fix typo

doc/man/knotc.8in

@@ -94,7 +94,7 @@ Show the zone status. Filters are \fB+role\fP, \fB+serial\fP, \fB+transaction\fP
 \fBzone\-check\fP [\fIzone\fP\&...]
 Test if the server can load the zone. Semantic checks are executed if enabled
 in the configuration. When invoked with flag \fB\-f\fP/\fB\-\-force\fP an error is
-returned when sematic check warning oppears. (*)
+returned when sematic check warning appears. (*)
 .TP
 \fBzone\-memstats\fP [\fIzone\fP\&...]
 Estimate memory use for the zone. (*)

doc/man_knotc.rst

@@ -71,7 +71,7 @@ Actions
 **zone-check** [*zone*...]
   Test if the server can load the zone. Semantic checks are executed if enabled
   in the configuration. When invoked with flag **-f**/**--force** an error is
-  returned when sematic check warning oppears. (*)
+  returned when sematic check warning appears. (*)
 
 **zone-memstats** [*zone*...]
   Estimate memory use for the zone. (*)