Address the following warning when running autoreconf:
configure.ac:191: warning: The macro `AC_FD_CC' is obsolete.
configure.ac:191: You should run autoupdate.
./lib/autoconf/general.m4:399: AC_FD_CC is expanded from...
m4/nasm.m4:4: AC_PROG_NASM is expanded from...
configure.ac:191: the top level