remove mainicon.png since it is not used anymore

Author: corrados

Jamulus.pro

@@ -683,7 +683,6 @@ DISTFILES += ChangeLog \
     src/res/ledbuttonnotpressed.png \
     src/res/ledbuttonpressed.png \
     src/res/fronticon.png \
-    src/res/mainicon.png \
     src/res/mixerboardbackground.png \
     src/res/VLEDBlack.png \
     src/res/VLEDBlackSmall.png \

src/aboutdlgbase.ui

@@ -21,7 +21,7 @@
   </property>
   <property name="windowIcon">
    <iconset resource="resources.qrc">
-    <normaloff>:/png/main/res/mainicon.png</normaloff>:/png/main/res/mainicon.png</iconset>
+    <normaloff>:/png/main/res/fronticon.png</normaloff>:/png/main/res/fronticon.png</iconset>
   </property>
   <property name="sizeGripEnabled">
    <bool>true</bool>

src/res/mainicon.png

@@ -119,7 +119,6 @@
     </qresource>
     <qresource prefix="/png/main">
         <file>res/fronticon.png</file>
-        <file>res/mainicon.png</file>
     </qresource>
     <qresource prefix="/png/flags">
         <file>res/flags/flagnone.png</file>