package/dvblast: fix musl build

In order to make dvblast build with the musl C library, use the
standard uintXX_t integer types instead of u_intXX_t.

Fixes:
    http://autobuild.buildroot.org/results/a43/a434372d84544116e7bb4a88c0ee437ae0578007/
    http://autobuild.buildroot.org/results/167/167efb284be47ae3e90fe7a8e6316e757b59cd3e/


    ...

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Julian Scheel <julian@jusst.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>