Option --disable-byterange fails if libcurl is not found
Option --disable-byterange fails if libcurl is not found

re: https://github.com/Unidata/netcdf-c/issues/1390

Change configure.ac to properly test for
combination of no-curl and disable-byterange.

Unidata/netcdf-c,Unidata/netcdf-c,Unidata/netcdf-c,Unidata/netcdf-c