WPrefs: convert workspacename.xpm X11 color name to hex

On window maker built without libxpm, a simple build-in xpm support is used.
That component does not support X11 color name thus when trying to load
that image we are getting a file corrupted error.
Colors manually converted using ref at
https://www.ehdp.com/methods/x11-colors/x11-colors-rgb-values-05.htm

WPrefs.app/xpm/workspacename.xpm

@@ -2,9 +2,9 @@
 static char *magick[] = {
 /* columns rows colors chars-per-pixel */
 "50 40 95 2",
-"   c Gray0",
+"   c #000000",
 ".  c #010101",
-"X  c Gray2",
+"X  c #050505",
 "o  c #040406",
 "O  c #070707",
 "+  c #0a0a0d",
@@ -20,14 +20,14 @@ static char *magick[] = {
 ":  c #4e4e4e",
 ">  c #505055",
 ",  c #585858",
-"<  c Gray37",
+"<  c #5e5e5e",
 "1  c #494d62",
 "2  c #545066",
 "3  c #57556f",
 "4  c #5d627c",
 "5  c #604e42",
-"6  c Gray39",
-"7  c Gray41",
+"6  c #636363",
+"7  c #696969",
 "8  c #646475",
 "9  c #7e6a63",
 "0  c #75746d",
@@ -67,36 +67,36 @@ static char *magick[] = {
 "D  c #989799",
 "F  c #9b9b9b",
 "G  c #999e98",
-"H  c Gray62",
+"H  c #9e9e9e",
 "J  c #9e9f9f",
 "K  c #8d8cba",
 "L  c #9995a0",
 "P  c #a2a2a3",
 "I  c #a7a7a8",
-"U  c Gray66",
+"U  c #a8a8a8",
 "Y  c #acacac",
-"T  c Gray68",
-"R  c Gray69",
+"T  c #adadad",
+"R  c #b0b0b0",
 "E  c #b2b2b2",
 "W  c #b4b4b4",
-"Q  c Gray71",
+"Q  c #b5b5b5",
 "!  c #b9b9b9",
-"~  c Gray73",
+"~  c #bababa",
 "^  c #bbbbbb",
 "/  c #a7a7c5",
 "(  c #acadcf",
 ")  c #c0c0c0",
 "_  c #c3c3c3",
 "`  c #c8c8c8",
-"'  c Gray79",
-"]  c Gray80",
+"'  c #c9c9c9",
+"]  c #cccccc",
 "[  c #dfdfdf",
 "{  c #e2e2e2",
-"}  c Gray91",
+"}  c #e8e8e8",
 "|  c #e9e9e9",
-" . c Gray95",
+" . c #f2f2f2",
 ".. c #fbfbfb",
-"X. c Gray100",
+"X. c #ffffff",
 /* pixels */
 "$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ } ",
 "$ 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 } } } } } } } } ",