devel/libantlr4: update to 4.9.1 release

Changes:
* Fixed ANTLRInputStream and ANTLRFileStream (target:cpp)
* Cpp target: allow building runtime with newer C++ standards (comp:build, target:cpp)
* travis: upgrade c++ build to focal & llvm 10 (comp:build, target:cpp)

devel/libantlr4/Makefile

 # Created by: Muhammad Moinur Rahman<5u623l20@gmail.com>
 
 PORTNAME=	antlr4
-PORTVERSION=	4.9
+PORTVERSION=	4.9.1
 DISTVERSIONPREFIX=	cpp-runtime-
 DISTVERSIONSUFFIX=	-source
 CATEGORIES=	devel
@@ -17,7 +17,7 @@ USES=		cmake compiler:c11 zip
 NO_WRKSUBDIR=	yes
 
 DOCSDIR=	${PREFIX}/share/doc/${PKGNAMEPREFIX}${PORTNAME}
-LIBVERSION=	4.9
+LIBVERSION=	${PORTVERSION}
 PLIST_SUB+=	LIBVERSION=${PORTVERSION}
 
 .include <bsd.port.mk>

devel/libantlr4/distinfo

-TIMESTAMP = 1606384483
-SHA256 (antlr4-cpp-runtime-4.9-source.zip) = 1055533089015f0837535a0126708678eb1212a80c70f42d8c4ce467d351cb7f
-SIZE (antlr4-cpp-runtime-4.9-source.zip) = 670109
-SHA256 (v3.1.1.zip) = b617897aecd29f4964e5b9a88c82bf238de4f6518651704d5eb07f24cbed5bf7
-SIZE (v3.1.1.zip) = 37070
+TIMESTAMP = 1629116842
+SHA256 (antlr4-cpp-runtime-4.9.1-source.zip) = 21647f9d5c55d13f2297e3f61e5dd68283e439983c27bd899f9c8a725bbea7b5
+SIZE (antlr4-cpp-runtime-4.9.1-source.zip) = 670184