package/avahi: drop unneeded am_cv_path_PYTHON

It is not used by the configure script and refer to PYTHON_TARGET_BINARY
which was dropped back in 2010 by commit e3418f69cf (python: convert to
autotargets, bump to 2.7.1, many improvements), so drop it.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/avahi/avahi.mk

@@ -107,7 +107,6 @@ endif
 ifeq ($(BR2_PACKAGE_PYTHON),y)
 AVAHI_CONF_ENV += \
 	am_cv_pathless_PYTHON=python \
-	am_cv_path_PYTHON=$(PYTHON_TARGET_BINARY) \
 	am_cv_python_version=$(PYTHON_VERSION) \
 	am_cv_python_platform=linux2 \
 	am_cv_python_pythondir=/usr/lib/python$(PYTHON_VERSION_MAJOR)/site-packages \