Log Message:
bmake: Update to 20200524.

This should help bootstrap on older platforms, such as IRIX with
the mipspro compiler.

2020-05-24  Simon J Gerraty  <sjg@beast.crufty.net>

	* configure.in: add AC_PROG_CC_C99 for mipspro compiler
	* dirname.c: remove include of namespace.h