audio/bsequencer-lv2: fix build with GCC architectures

C++11 compiler is required:
cc1plus: error: unrecognized command line option "-std=c++11"

include sys/types.h is required by GCC for uint in src/BWidgets/ChoiceBox.cpp, src/BWidgets/ImageIcon.cpp and src/BWidgets/ListBox.cpp.

PR:		239440
Approved by:	linimon (mentor), yuri (maintainer)
Differential Revision:	https://reviews.freebsd.org/D21066

audio/bsequencer-lv2/Makefile

@@ -15,7 +15,7 @@ LICENSE_FILE=	${WRKSRC}/LICENSE
 
 BUILD_DEPENDS=	lv2>0:audio/lv2
 
-USES=		gmake gnome pkgconfig
+USES=		compiler:c++11-lang gmake gnome pkgconfig
 USE_GITHUB=	yes
 GH_ACCOUNT=	sjaehn
 GH_PROJECT=	BSEQuencer

audio/bsequencer-lv2/files/patch-src_BWidgets_ChoiceBox.cpp

@@ -0,0 +1,10 @@
+--- src/BWidgets/ChoiceBox.cpp.orig	2019-07-25 10:03:27 UTC
++++ src/BWidgets/ChoiceBox.cpp
+@@ -16,6 +16,7 @@
+  */
+ 
+ #include "ChoiceBox.hpp"
++#include <sys/types.h>
+ 
+ namespace BWidgets
+ {

audio/bsequencer-lv2/files/patch-src_BWidgets_ImageIcon.cpp

@@ -0,0 +1,10 @@
+--- src/BWidgets/ImageIcon.cpp.orig	2019-07-25 10:05:26 UTC
++++ src/BWidgets/ImageIcon.cpp
+@@ -16,6 +16,7 @@
+  */
+ 
+ #include "ImageIcon.hpp"
++#include <sys/types.h>
+ 
+ namespace BWidgets
+ {

audio/bsequencer-lv2/files/patch-src_BWidgets_ListBox.cpp

@@ -0,0 +1,10 @@
+--- src/BWidgets/ListBox.cpp.orig	2019-07-25 10:08:28 UTC
++++ src/BWidgets/ListBox.cpp
+@@ -16,6 +16,7 @@
+  */
+ 
+ #include "ListBox.hpp"
++#include <sys/types.h>
+ 
+ namespace BWidgets
+ {