tinyalsa: fix musl build

Add upstream patch adding missing header include.

Fixes:
http://autobuild.buildroot.net/results/042/04259ddbdf24afc507b0f21e1f5ba8738ec492b1/
http://autobuild.buildroot.net/results/371/371a1eab885d1a6b5b06bdab6c2280b20593eed4/
http://autobuild.buildroot.net/results/377/37743b3e73fcb0df9fd50113e082eac712c25e35/



Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>