python, python3: build with tzset support

This patch adds support for time.tzset() in Python 2.7 and Python 3.

The Python configure script sets ac_cv_working_tzset to 'no' when
cross compiling, although it should be available and work with all
toolchains supported by Buildroot (?).
The patch below pre-sets the variable so that time.tzset() works.

[Thomas: adjust commit log.]

Signed-off-by: Henry Margies <henry.margies@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/python/python.mk

@@ -121,7 +121,8 @@ endif
 PYTHON_CONF_ENV += \
 	ac_cv_have_long_long_format=yes \
 	ac_cv_file__dev_ptmx=yes \
-	ac_cv_file__dev_ptc=yes
+	ac_cv_file__dev_ptc=yes \
+	ac_cv_working_tzset=yes
 
 PYTHON_CONF_OPT += \
 	--without-cxx-main 	\

package/python3/python3.mk

@@ -96,6 +96,7 @@ PYTHON3_CONF_ENV += \
 	ac_cv_have_long_long_format=yes \
 	ac_cv_file__dev_ptmx=yes \
 	ac_cv_file__dev_ptc=yes \
+	ac_cv_working_tzset=yes
 
 PYTHON3_CONF_OPT += \
 	--without-ensurepip	\