Fix "knwon" typo and add a check in tools/patcheck

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavcodec/alsdec.c

@@ -308,7 +308,7 @@ static av_cold int read_specific_config(ALSDecContext *ctx)
     skip_bits_long(&gb, 32); // sample rate already known
     sconf->samples              = get_bits_long(&gb, 32);
     avctx->channels             = m4ac.channels;
-    skip_bits(&gb, 16);      // number of channels already knwon
+    skip_bits(&gb, 16);      // number of channels already known
     skip_bits(&gb, 3);       // skip file_type
     sconf->resolution           = get_bits(&gb, 3);
     sconf->floating             = get_bits1(&gb);

libavcodec/mjpegdec.c

@@ -1423,9 +1423,9 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
             av_log(s->avctx, AV_LOG_INFO,
                    "Pegasus lossless jpeg header found\n");
         skip_bits(&s->gb, 16); /* version ? */
-        skip_bits(&s->gb, 16); /* unknwon always 0? */
+        skip_bits(&s->gb, 16); /* unknown always 0? */
-        skip_bits(&s->gb, 16); /* unknwon always 0? */
+        skip_bits(&s->gb, 16); /* unknown always 0? */
-        skip_bits(&s->gb, 16); /* unknwon always 0? */
+        skip_bits(&s->gb, 16); /* unknown always 0? */
         switch (get_bits(&s->gb, 8)) {
         case 1:
             s->rgb         = 1;

libavformat/mxfenc.c

@@ -170,7 +170,7 @@ static const MXFContainerEssenceEntry mxf_essence_container_uls[] = {
       { 0x06,0x0E,0x2B,0x34,0x01,0x02,0x01,0x01,0x0D,0x01,0x03,0x01,0x06,0x01,0x10,0x00 },
       { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x04,0x02,0x02,0x01,0x00,0x00,0x00,0x00 },
       mxf_write_generic_sound_desc },
-    // DV Unknwon
+    // DV Unknown
     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x02,0x7F,0x01 },
       { 0x06,0x0E,0x2B,0x34,0x01,0x02,0x01,0x01,0x0D,0x01,0x03,0x01,0x18,0x01,0x01,0x00 },
       { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x04,0x01,0x02,0x02,0x02,0x00,0x00,0x00 },

tools/patcheck

@@ -67,7 +67,7 @@ $EGREP $OPT '^\+ *(const *|)static' $*| $EGREP --color=always '[^=]= *(0|NULL)[^
 cat $TMP
 hiegrep '# *ifdef * (HAVE|CONFIG)_' 'ifdefs that should be #if' $*
 
-hiegrep '\b(awnser|cant|dont|wont|usefull|successfull|occured|teh|alot|wether|skiped|skiping|heigth|informations|colums|loosy|loosing|ouput|seperate|preceed|upto|paket|posible|unkown|inpossible|dimention|acheive|funtions|overriden|outputing|seperation|initalize|compatibilty|bistream)\b' 'common typos' $*
+hiegrep '\b(awnser|cant|dont|wont|usefull|successfull|occured|teh|alot|wether|skiped|skiping|heigth|informations|colums|loosy|loosing|ouput|seperate|preceed|upto|paket|posible|unkown|inpossible|dimention|acheive|funtions|overriden|outputing|seperation|initalize|compatibilty|bistream|knwon|unknwon)\b' 'common typos' $*
 
 hiegrep 'av_log\( *NULL' 'Missing context in av_log' $*
 hiegrep '[^sn]printf' 'Please use av_log' $*