*/*: update for virtual/zlib

Update done using:

```
git grep -l sys-libs/zlib sys-* | xargs sed -i -e s@sys-libs/zlib@virtual/zlib@g
git grep -l virtual/zlib-ng sys-* | xargs sed -i -e s@virtual/zlib-ng@sys-libs/zlib-ng@g
git diff --name-only | xargs copybump
git diff --name-only | xargs grep -l PYTHON_COMPAT | xargs gpy-impl -@dead
pkgcheck scan --commits -c SourcingCheck,VisibilityCheck --exit error
```

Signed-off-by: Paul Zander <negril.nx+gentoo@gmail.com>

games-emulation/RetroArch/RetroArch-1.19.1.ebuild

@@ -1,4 +1,4 @@
-# Copyright 1999-2024 Gentoo Authors
+# Copyright 1999-2025 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
@@ -74,7 +74,7 @@ RDEPEND="
 	)
 	xinerama? ( x11-libs/libXinerama:0= )
 	xv? ( x11-libs/libXv )
-	zlib? ( sys-libs/zlib:0= )
+	zlib? ( virtual/zlib:0= )
 "
 DEPEND="${RDEPEND}"
 BDEPEND="

games-emulation/RetroArch/RetroArch-1.20.0.ebuild

@@ -1,4 +1,4 @@
-# Copyright 1999-2024 Gentoo Authors
+# Copyright 1999-2025 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
@@ -75,7 +75,7 @@ RDEPEND="
 	)
 	xinerama? ( x11-libs/libXinerama:0= )
 	xv? ( x11-libs/libXv )
-	zlib? ( sys-libs/zlib:0= )
+	zlib? ( virtual/zlib:0= )
 "
 DEPEND="${RDEPEND}"
 BDEPEND="

games-emulation/RetroArch/RetroArch-1.21.0.ebuild

@@ -75,7 +75,7 @@ RDEPEND="
 	)
 	xinerama? ( x11-libs/libXinerama:0= )
 	xv? ( x11-libs/libXv )
-	zlib? ( sys-libs/zlib:0= )
+	zlib? ( virtual/zlib:0= )
 "
 DEPEND="${RDEPEND}"
 BDEPEND="

games-emulation/dosbox-x/dosbox-x-2025.05.03.ebuild

@@ -52,7 +52,7 @@ COMMON_DEPEND="
 	media-libs/libsdl2[X,alsa,opengl?,sound,threads(+),video]
 	media-libs/sdl2-net
 	net-libs/libpcap
-	sys-libs/zlib
+	virtual/zlib
 	X? (
 		x11-libs/libX11
 		x11-libs/libXrandr

games-emulation/dosbox-x/dosbox-x-2025.10.07.ebuild

@@ -52,7 +52,7 @@ COMMON_DEPEND="
 	media-libs/libsdl2[X,alsa,opengl?,sound,threads(+),video]
 	media-libs/sdl2-net
 	net-libs/libpcap
-	sys-libs/zlib
+	virtual/zlib
 	X? (
 		x11-libs/libX11
 		x11-libs/libXrandr

games-emulation/dosbox-x/dosbox-x-9999.ebuild

@@ -1,4 +1,4 @@
-# Copyright 2022-2024 Gentoo Authors
+# Copyright 2022-2025 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
@@ -52,7 +52,7 @@ COMMON_DEPEND="
 	media-libs/libsdl2[X,alsa,opengl?,sound,threads(+),video]
 	media-libs/sdl2-net
 	net-libs/libpcap
-	sys-libs/zlib
+	virtual/zlib
 	X? (
 		x11-libs/libX11
 		x11-libs/libXrandr

games-emulation/eden/eden-0.0.4_rc2.ebuild

@@ -41,7 +41,7 @@ RDEPEND="
 	media-video/ffmpeg
 	net-libs/enet
 	net-libs/mbedtls:3
-	sys-libs/zlib
+	virtual/zlib
 
 	camera? ( dev-qt/qtmultimedia:6 )
 	cubeb? ( media-libs/cubeb )

games-emulation/flycast/flycast-9999.ebuild

@@ -24,7 +24,7 @@ DEPEND="
 	dev-libs/xxhash
 	media-libs/libsdl2
 	net-libs/miniupnpc
-	sys-libs/zlib
+	virtual/zlib
 	alsa? ( media-libs/alsa-lib )
 	ao? ( media-libs/libao )
 	lua? ( ${LUA_DEPS} )

games-emulation/rpcs3/rpcs3-0.0.37.ebuild

@@ -68,7 +68,7 @@ DEPEND="
 	media-video/ffmpeg:=
 	net-misc/curl
 	llvm-core/llvm:=
-	sys-libs/zlib
+	virtual/zlib
 	virtual/libusb:1
 	x11-libs/libX11
 	faudio? ( app-emulation/faudio )

games-emulation/rpcs3/rpcs3-0.0.38.ebuild

@@ -67,7 +67,7 @@ DEPEND="
 	net-libs/miniupnpc:=
 	net-misc/curl
 	llvm-core/llvm:=
-	sys-libs/zlib
+	virtual/zlib
 	virtual/libusb:1
 	x11-libs/libX11
 	faudio? ( app-emulation/faudio )

games-emulation/rpcs3/rpcs3-9999.ebuild

@@ -67,7 +67,7 @@ DEPEND="
 	net-libs/miniupnpc:=
 	net-misc/curl
 	llvm-core/llvm:=
-	sys-libs/zlib
+	virtual/zlib
 	virtual/libusb:1
 	x11-libs/libX11
 	faudio? ( app-emulation/faudio )