Bugfix: Use %{name} in lieu of %{header_install_path}
Bugfix: Use %{name} in lieu of %{header_install_path}

The variable `header_install_path` was uninitialized
and thus resulted in rpmbuild not being able to
find the header files.

sociomantic/libdrizzle-redux,sociomantic/libdrizzle-redux,sociomantic/libdrizzle-redux