package/fluidsynth: bump to version 2.3.7

For change log since v2.3.6, see:
https://github.com/FluidSynth/fluidsynth/releases/tag/v2.3.7

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
2 files changed