emulators/dosbox-staging: update to 0.77.1 (bugfix release)

Release notes: https://dosbox-staging.github.io/v0-77-1/

emulators/dosbox-staging/Makefile

 PORTNAME=	dosbox-staging
 DISTVERSIONPREFIX=	v
-DISTVERSION=	0.77.0
+DISTVERSION=	0.77.1
 CATEGORIES=	emulators
 
 MAINTAINER=	makc@FreeBSD.org

emulators/dosbox-staging/distinfo

-TIMESTAMP = 1626517418
-SHA256 (dosbox-staging-dosbox-staging-v0.77.0_GH0.tar.gz) = 85e1739f5dfd7d96b752b2b0e12aad6f95c7770b47fcdaf978d4128d7890d986
-SIZE (dosbox-staging-dosbox-staging-v0.77.0_GH0.tar.gz) = 2579927
+TIMESTAMP = 1630255597
+SHA256 (dosbox-staging-dosbox-staging-v0.77.1_GH0.tar.gz) = 85359efb7cd5c5c0336d88bdf023b7b462a8233490e00274fef0b85cca2f5f3c
+SIZE (dosbox-staging-dosbox-staging-v0.77.1_GH0.tar.gz) = 2622418