When we setTextEntry on a combo box, move the cursor to the beginning of the new text.

This fixes the login location combo box not displaying the location cleanly after appending coordinates and such.

indra/llui/llcombobox.cpp

@@ -937,6 +937,7 @@ void LLComboBox::setTextEntry(const LLStringExplicit& text)
 	if (mTextEntry)
 	{
 		mTextEntry->setText(text);
+		mTextEntry->setCursor(0); // Singu Note: Move the cursor over to the beginning
 		mHasAutocompletedText = FALSE;
 		updateSelection();
 	}