package/libcue: is not parallel-safe

package/libcue: is not parallel-safe

The last commit before the 1.4.0 release was to disable parallel build [1]

[1] https://github.com/lipnitsk/libcue/commit/bebbc18a8c00a0b8c26bc6191af68c6a83629b40

Fixes:
http://autobuild.buildroot.net/results/f25/f256037ca3d49f96add8ca2e2f9c980f5f9d764e
http://autobuild.buildroot.net/results/d84/d84c7d0cb9cf5fa9996c42149eda5295700516f5

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>