spelling.txt: Remove some duplicate entries

Found when Colin King fixed a typo for falied/failed
and a git grep showed 2 entries in this file.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

scripts/spelling.txt

@@ -596,7 +596,6 @@ extenstion||extension
 extracter||extractor
 faied||failed
 faield||failed
-falied||failed
 faild||failed
 failded||failed
 failer||failure
@@ -793,7 +792,6 @@ interrup||interrupt
 interrups||interrupts
 interruptted||interrupted
 interupted||interrupted
-interupt||interrupt
 intial||initial
 intialisation||initialisation
 intialised||initialised
@@ -968,7 +966,6 @@ occurd||occurred
 occured||occurred
 occurence||occurrence
 occure||occurred
-occured||occurred
 occuring||occurring
 offser||offset
 offet||offset
@@ -1437,7 +1434,6 @@ udpate||update
 uesd||used
 uknown||unknown
 usccess||success
-usupported||unsupported
 uncommited||uncommitted
 uncompatible||incompatible
 unconditionaly||unconditionally