package/python-asgiref: properly order "depends on" vs. bool

package/python-asgiref: properly order "depends on" vs. bool

This fixes a check-package warning introduced by commit
9b746f8 ("package/python-asgiref: drop Python 2 support")
Fixes:

$: ./utils/check-package package/python-asgiref/*
package/python-asgiref/Config.in:3: attributes order: type, default, depends on, select, help (http://nightly.buildroot.org/#_config_files)
34 lines processed
1 warnings generated

Signed-off-by: Pierre-Jean Texier <pjtexier@koncepto.io>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>