pcre: Fix compile of libpcrecpp

If the cpp lib is added after pcre is first compiled, pcre will
not be reconfigured and the build will fail.
Fix this by always building the cpp parts.

Signed-off-by: Jan Kardell <jan.kardell@telliq.com>

libs/pcre/Makefile

@@ -55,12 +55,8 @@ CONFIGURE_ARGS += \
 	--enable-unicode-properties \
 	--enable-pcre16 \
 	--with-match-limit-recursion=16000 \
+	--enable-cpp
 
-ifneq ($(CONFIG_PACKAGE_libpcrecpp),)
-  CONFIGURE_ARGS+= --enable-cpp
-else
-  CONFIGURE_ARGS+= --disable-cpp
-endif
 
 MAKE_FLAGS += \
 	CFLAGS="$(TARGET_CFLAGS)"