Update to 3.2.6

While here:

• Add license
• Add the missing SDL option to OPTIONS_DEFINE
• Fix ESOUND option
• Fix build of NAS option with Clang < 4.0
• The configure script says this configure: WARNING: unrecognized options: --with-cxxflags so remove it from CONFIGURE_ARGS
• Regenerate patches

Changes: http://www.mp3blaster.org/2017/05/its-only-been-8-years.html
PR: 219808
Approved by: lme (mentor), novel (maintainer)
Differential Revision: https://reviews.freebsd.org/D11076