transmission: add p{read,write}v2 syscalls to seccomp filter

Tracing Transmission 4.11 showed the Transmission is started to use
the pwritev2 syscall for better write performance.
Add pwritev2 and preadv2 (which may be used as well, and anyway
doesn't hurt) to the list of allowed syscalls.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
(cherry picked from commit 9e84e22a78)

net/transmission/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=transmission
 PKG_VERSION:=4.1.1
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=https://github.com/transmission/transmission/releases/download/$(PKG_VERSION)/

net/transmission/files/transmission-daemon.json

@@ -75,9 +75,11 @@
 				"poll",
 				"ppoll",
 				"pread64",
+				"preadv2",
 				"prlimit64",
 				"pselect6",
 				"pwrite64",
+				"pwritev2",
 				"quotactl",
 				"read",
 				"readlink",