library: Define 'solSACapability' as '0'

"according to a comment in f_gmm_attach() there's an encoder problem if it's omit.  This sounds like the ts_GMM_ATTACH_REQ()
should be changed to define solSACapability as '0' insteads of omit.  At that point none of the users of ts_GMM_ATTACH_REQ
will need to manually modify it anymore."
(quote: hwelte on Gerrit (https://gerrit.osmocom.org/c/osmo-ttcn3-hacks/+/31199/comments/17ed155d_cc58810a))

Related: OS#4221
Change-Id: I9eaa39274456e5cc0a1cf025bf956970efc4a51f
diff --git a/library/L3_Templates.ttcn b/library/L3_Templates.ttcn
index 1ea8b82..de7063f 100644
--- a/library/L3_Templates.ttcn
+++ b/library/L3_Templates.ttcn
@@ -2209,7 +2209,7 @@
 	smCapabilitiesviaGPRSChannels := '0'B,
 	ucs2Support := '1'B,
 	ssScreeningIndicator := '01'B,
-	solSACapability := omit,
+	solSACapability := '0'B,
 	revisionLevelIndicatior := omit,
 	pFCFeatureMode := omit,
 	extendedGEAbits := omit,