postgresql_17: 17.7 -> 17.8

Release Notes:
https://github.com/postgres/postgres/blob/REL_17_STABLE/doc/src/sgml/release-17.sgml

Security: CVE-2026-2003, CVE-2026-2004, CVE-2026-2005, CVE-2026-2006,
CVE-2026-2007

pkgs/servers/sql/postgresql/17.nix

@@ -1,7 +1,8 @@
 import ./generic.nix {
-  version = "17.7";
-  rev = "refs/tags/REL_17_7";
-  hash = "sha256-W+505LAeiO5ln7wBhxZLv/p3GxiJp8MFfCGVDyvHREg=";
+  version = "17.8";
+  # rev = "refs/tags/REL_17_8";
+  rev = "6af885119b52a2a6229959670ba3ae5e36bf9806";
+  hash = "sha256-4lV1/xRmMsc5rgY3RB6WMigTXHgHjh9bmR6nzL82Rs4=";
   muslPatches = {
     dont-use-locale-a = {
       url = "https://git.alpinelinux.org/aports/plain/main/postgresql17/dont-use-locale-a-on-musl.patch?id=d69ead2c87230118ae7f72cef7d761e761e1f37e";

pkgs/servers/sql/postgresql/generic.nix

@@ -87,7 +87,7 @@ let
         # Building with JIT in pkgsStatic fails like this:
         #   fatal error: 'stdio.h' file not found
         && !stdenv.hostPlatform.isStatic,
-      llvmPackages_20,
+      llvmPackages,
       nukeReferences,
       overrideCC,
 
@@ -163,14 +163,6 @@ let
 
       dlSuffix = if olderThan "16" then ".so" else stdenv.hostPlatform.extensions.sharedLibrary;
 
-      # Pin LLVM 20 until upstream has fully resolved:
-      # https://www.postgresql.org/message-id/flat/d25e6e4a-d1b4-84d3-2f8a-6c45b975f53d%40applied-asynchrony.com
-      # Currently still a problem on aarch64.
-      # TODO: Remove with next minor releases
-      llvmPackages = lib.warnIf (
-        version == "17.8"
-      ) "PostgreSQL: Is the pin for LLVM 20 still needed?" llvmPackages_20;
-
       stdenv' =
         if !stdenv.cc.isClang then
           overrideCC llvmPackages.stdenv (