libssh: needs shared library support

libssh builds libssh.so unconditionally.

Fixes:
http://autobuild.buildroot.net/results/7c7/7c7da08c71b5378b68631e3844088307080f6f9e/
http://autobuild.buildroot.net/results/a19/a19c619f4561f5426236b958f09cab4c095a63cc/
http://autobuild.buildroot.net/results/d6d/d6dd4a9b787d654b4173c03174a2fd72bdc017b3/

and more.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libssh/Config.in

@@ -1,6 +1,7 @@
 config BR2_PACKAGE_LIBSSH
 	bool "libssh"
 	depends on BR2_USE_MMU # fork()
+	depends on !BR2_STATIC_LIBS
 	# Either OpenSSL or libgcrypt are mandatory
 	select BR2_PACKAGE_LIBGCRYPT if !BR2_PACKAGE_OPENSSL
 	help
@@ -10,3 +11,7 @@ config BR2_PACKAGE_LIBSSH
 	  secure and transparent tunnel for your remote applications.
 
 	  http://www.libssh.org/
+
+comment "libssh needs a toolchain w/ dynamic library"
+	depends on BR2_USE_MMU
+	depends on BR2_STATIC_LIBS