libosmogb: make build conditional, disable in embedded build

when we build for osmocom-bb cross-compilation, we don't have
sockets nor netinet/in.h and thus NS/BSSGP make no sense...

configure.ac

@@ -137,6 +137,14 @@ AC_ARG_ENABLE(utilities,
         [enable_utilities=$enableval], [enable_utilities="yes"])
 AM_CONDITIONAL(ENABLE_UTILITIES, test x"$enable_utilities" = x"yes")
 
+AC_ARG_ENABLE(gb,
+        [AS_HELP_STRING(
+                [--disable-gb],
+                [Disable building Gb library],
+        )],
+        [enable_gb=$enableval], [enable_gb="yes"])
+AM_CONDITIONAL(ENABLE_GB, test x"$enable_gb" = x"yes")
+
 AC_ARG_ENABLE(embedded,
 	[AS_HELP_STRING(
 		[--enable-embedded],
@@ -152,6 +160,7 @@ then
 	AM_CONDITIONAL(ENABLE_VTY, false)
 	AM_CONDITIONAL(ENABLE_TALLOC, false)
 	AM_CONDITIONAL(ENABLE_UTILITIES, false)
+	AM_CONDITIONAL(ENABLE_GB, false)
 	AC_DEFINE([PANIC_INFLOOP],[1],[Use infinite loop on panic rather than fprintf/abort])
 fi
 

src/gb/Makefile.am

@@ -8,6 +8,7 @@ AM_CFLAGS = -Wall ${GCC_FVISIBILITY_HIDDEN} -fno-strict-aliasing
 # FIXME: this should eventually go into a milenage/Makefile.am
 noinst_HEADERS = common_vty.h
 
+if ENABLE_GB
 lib_LTLIBRARIES = libosmogb.la
 
 libosmogb_la_LDFLAGS = -Wl,--version-script=$(srcdir)/libosmogb.map -version-info $(LIBVERSION)
@@ -19,6 +20,7 @@ libosmogb_la_LIBADD = \
 libosmogb_la_SOURCES = gprs_ns.c gprs_ns_frgre.c gprs_ns_vty.c \
 		  gprs_bssgp.c gprs_bssgp_util.c gprs_bssgp_vty.c \
 		  gprs_bssgp_bss.c common_vty.c
+endif
 
 EXTRA_DIST = libosmogb.map