Perform the QRgb to hex conversion in an endian-independent way.

--- kiconthemes-5.116.0/src/kiconloader.cpp.old	2024-05-04 06:40:07.000000000 -0500
+++ kiconthemes-5.116.0/src/kiconloader.cpp	2025-06-30 05:00:25.377715342 -0500
@@ -77,7 +77,8 @@
 {
     static const char hexLookup[] = "0123456789abcdef";
     buffer += 7;
-    uchar *colorFields = reinterpret_cast<uchar *>(&colorData);
+    uchar fields[4] = {qBlue(colorData), qGreen(colorData), qRed(colorData), qAlpha(colorData)};
+    uchar *colorFields = &fields[0];
 
     for (int i = 0; i < 4; i++) {
         *buffer-- = hexLookup[*colorFields & 0xf];