commit e49ce141 breaks cross compiling
the linux kernel on darwin hosts.
This fix introduce some minimal glue to adopt linker section handling
for darwin hosts.

Signed-off-by: Andreas Bießmann <andreas@biessmann.de>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Jochen Friedrich <jochen@scram.de>
CC: Samuel Ortiz <sameo@linux.intel.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Bernhard Walle <bernhard@bwalle.de>