nasm: bump version to 2.10.01, remove dummy target package

The target package was only present because at the time 'nasm' was
packaged, there was a bug in the package infrastructure that prevented
a package from having a host only variant. This has been fixed since
then, so we can get rid of the useless dummy target package.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>