dev-qt/qtwebengine: fix glibc2.41 patch for older glibc

(actually) import from www-client/chromium this time, had missed
that the final used patch was different than the one on the bug.

No need for another revbump given it'd have just failed to build
if <2.41, and was fine if using 2.41.

Bug:  https://bugs.gentoo.org/949654
Thanks-to: Sam James <sam@gentoo.org>
Fixes: 030898ec7d
Signed-off-by: Ionen Wolkens <ionen@gentoo.org>

dev-qt/qtwebengine/files/qtwebengine-6.8.2-glibc2.41.patch

@@ -2,19 +2,21 @@ https://bugs.gentoo.org/949654
 
 Quick downstream fix for now. Hasn't been sent to upstream(s) yet
 as of the writing of this, but believe it should happen soon.
-
-From 6c7a3a3a733cf33e9355f497815700e5e26e7c3d Mon Sep 17 00:00:00 2001
-From: Mike Lothian <mike@fireburn.co.uk>
-Date: Wed, 12 Feb 2025 13:52:01 +0000
-Subject: [PATCH] Test fix
 --- a/src/3rdparty/chromium/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions.cc
 +++ b/src/3rdparty/chromium/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions.cc
-@@ -238,7 +238,7 @@ ResultExpr RestrictMmapFlags() {
-   // TODO(davidung), remove MAP_DENYWRITE with updated Tegra libraries.
+@@ -36,4 +36,8 @@
+ #include "sandbox/linux/system_headers/linux_time.h"
+ 
++#if !defined(MAP_DROPPABLE)
++#define MAP_DROPPABLE	0x08    // Zero memory under memory pressure.
++#endif
++
+ #if (BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS_LACROS)) && \
+     !defined(__arm__) && !defined(__aarch64__) &&             \
+@@ -239,5 +243,5 @@
    const uint64_t kAllowedMask = MAP_SHARED | MAP_PRIVATE | MAP_ANONYMOUS |
                                  MAP_STACK | MAP_NORESERVE | MAP_FIXED |
 -                                MAP_DENYWRITE | MAP_LOCKED |
 +                                MAP_DENYWRITE | MAP_LOCKED | MAP_DROPPABLE |
                                  kArchSpecificAllowedMask;
    const Arg<int> flags(3);
-   return If((flags & ~kAllowedMask) == 0, Allow()).Else(CrashSIGSYS());