package/belle-sip: remove package

belle-sip was only needed as a dependency of linphone, as is anyway
bundled in more recent versions of linphone, making a separate package
unnecessary.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit ffa6824417)
Signed-off-by: Thomas Perale <thomas.perale@mind.be>

DEVELOPERS

@@ -999,7 +999,6 @@ F:	package/openzwave/
 
 N:	Fabrice Fontaine <fontaine.fabrice@gmail.com>
 F:	package/bearssl/
-F:	package/belle-sip/
 F:	package/belr/
 F:	package/boinc/
 F:	package/cairo/