ympd: needs <dlfcn.h>

Add a dependency on !BR2_STATIC_LIBS, since <dlfcn.h> is used. While
we're at it, we also fix the comment which was lacking the BR2_USE_MMU
dependency.

Fixes:

  http://autobuild.buildroot.org/results/30853c1011544f8b6a5d3b3852af93bef4c0f5cb/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/ympd/Config.in

@@ -3,9 +3,11 @@ config BR2_PACKAGE_YMPD
 	select BR2_PACKAGE_LIBMPDCLIENT
 	depends on BR2_USE_MMU # fork()
 	depends on BR2_TOOLCHAIN_HAS_THREADS
+	depends on !BR2_STATIC_LIBS
 	help
 	  ympd, a standalone MPD Web GUI written in C, utilizing
 	  Websockets and Bootstrap/JS
 
-comment "ympd needs a toolchain w/ threads"
-	depends on !BR2_TOOLCHAIN_HAS_THREADS
+comment "ympd needs a toolchain w/ threads, dynamic library"
+	depends on BR2_USE_MMU
+	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS