mutt: fix build and convert to autotools

mutt has been upgraded, but the mutt-1.5.16-makedoc-hostcc.patch
wasn't upgraded accordingly, causing build failures in the
documentation. Therefore, we add a new patch
mutt-1.5.17+20080114-nodoc.patch that disables the construction of the
documentation.

As this patch modifies Makefile.am, we need to autoreconf the
package. The simplest and cleanest way to do this is to convert the
package to the autotools infrastructure.

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