boost169 do not respect configure.cc

[catap (Kirill A. Korinsky)]

My system had Ryan's wrapper to catch wrong GCC as it described here: ​https://trac.macports.org/wiki/UsingTheRightCompiler

An attempt to build from scratch boost169 fails on configuration stage with error:

###
### Using 'darwin' toolset.
###
rm -rf bootstrap
mkdir bootstrap
cc -o bootstrap/jam0 command.c compile.c constants.c debug.c execcmd.c frames.c function.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c object.c option.c output.c parse.c pathsys.c regexp.c rules.c scan.c search.c subst.c timestamp.c variable.c modules.c strings.c filesys.c builtins.c class.c cwd.c native.c md5.c w32_getreg.c modules/set.c modules/path.c modules/regex.c modules/property-set.c modules/sequence.c modules/order.c execunix.c fileunix.c pathunix.c
cc -o bootstrap/jam0 command.c compile.c constants.c debug.c execcmd.c frames.c function.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c object.c option.c output.c parse.c pathsys.c regexp.c rules.c scan.c search.c subst.c timestamp.c variable.c modules.c strings.c filesys.c builtins.c class.c cwd.c native.c md5.c w32_getreg.c modules/set.c modules/path.c modules/regex.c modules/property-set.c modules/sequence.c modules/order.c execunix.c fileunix.c pathunix.c
cc: Error: You should be using ${configure.cc}
See https://trac.macports.org/wiki/UsingTheRightCompiler

[cooljeanius (Eric Gallager)]

I guess this is probably the root cause of the latest build failure I'm seeing with it?