[0.4.7][MMSYS] Fix combo box and play icon on "Sound" properties page (#2690)

[0.4.7][MMSYS] Fix combo box and play icon on "Sound" properties page (#2690)

CORE-16935

I merged that back, because at least the play-icon was a regression.
It regressed by SVN r68073 == git 888c2fb9675536c1132222860378b85d1129d53e

Ftr we did not always use an icon here, but instead earlier we just had some
font glyph displaying the play-symbol. It was once changed to icon to improve
display for some asian localization (japanese? iirc).

fix picked from commit 0.4.15-dev-86-g bdb4da009acc13136a07f98a3c710687b75a7848

The patch also decreases binary size
mmsys.cpl binary size in bytes RosBE2.1.6 GCC4.7.2 dbg I18N=all:
0.4.13  old 786.944   patched 782.848
0.4.12  old 786.944   patched 782.848
0.4.11  old 745.472   patched 741.376
0.4.10  old 745.472   patched 741.376
0.4. 9  old 745.472   patched 741.376
0.4. 8  old 745.472   patched 741.376
0.4. 7  old 745.984   patched 741.888