Fix invalid comparator in FullscreenUI game list sort

The game list comparator previously used >= when sorting by CRC in
descending order. This violates the requirements of a strict weak
ordering, as defined by the C++ standard, which mandates that the
comparator must be irreflexive: comp(x, x) must always return false.

Using >= causes comp(a, b) and comp(b, a) to both return true when
a == b, which breaks the irreflexivity and can invalidate the
assumptions made by std::sort. This may lead to undefined behavior,
including memory corruption or segmentation faults.

Replace >= with > to ensure the comparator satisfies the strict weak
ordering requirement, restoring correctness and stability in game list
sorting behavior.

pcsx2/ImGui/FullscreenUI.cpp

@@ -6285,7 +6285,7 @@ void FullscreenUI::PopulateGameListEntryList()
 				case 4: // CRC
 				{
 					if (lhs->crc != rhs->crc)
-						return reverse ? (lhs->crc >= rhs->crc) : (lhs->crc < rhs->crc);
+						return reverse ? (lhs->crc > rhs->crc) : (lhs->crc < rhs->crc);
 				}
 				break;