ci: update Linux image to Fedora 40

Drop ROCm HIP packages from the image in favor of the dedicated
Fedora 39 base image we use for that job.

Issue: #25932

.gitlab/ci/docker/fedora40/Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-ARG BASE_IMAGE=fedora:39
+ARG BASE_IMAGE=fedora:40
 
 FROM ${BASE_IMAGE} AS dnf-cache
 # Populate DNF cache w/ the fresh metadata and prefetch packages.

.gitlab/ci/docker/fedora40/deps_packages.lst

@@ -11,7 +11,6 @@ clang-tools-extra
 clang-tools-extra-devel
 compiler-rt
 flang
-flang-devel
 gcc-c++
 git-core
 llvm-devel
@@ -32,6 +31,7 @@ zlib-devel
 
 # Install documentation tools.
 python3-sphinx
+python3-sphinxcontrib-qthelp
 texinfo
 qt5-qttools-devel
 qt6-qttools-devel
@@ -49,13 +49,6 @@ which
 # Install ASM_NASM language toolchain.
 nasm
 
-# Install HIP language toolchain.
-hsakmt-devel
-lld
-rocm-comgr-devel
-rocm-hip-devel
-rocm-runtime-devel
-
 # Packages needed to test CTest.
 breezy
 subversion
@@ -99,6 +92,7 @@ libcurl-devel
 libicu-devel
 libinput-devel systemd-devel
 libjpeg-turbo-devel
+libomp-devel
 libpng-devel
 opensp-devel
 postgresql-server-devel
@@ -126,3 +120,6 @@ wxGTK-devel
 xalan-c-devel
 xerces-c-devel
 xz-devel
+
+# Packages needed to test third-party binaries.
+ncurses-compat-libs

.gitlab/ci/docker/fedora40/install_iwyu.sh

@@ -18,13 +18,13 @@ readonly llvm_version="$( echo "$llvm_full_version" | cut -d. -f-1 )"
 git checkout "clang_$llvm_version"
 git apply <<EOF
 diff --git a/iwyu_driver.cc b/iwyu_driver.cc
-index 42fea35..fbb77a9 100644
+index dd4b046..cfd568a 100644
 --- a/iwyu_driver.cc
 +++ b/iwyu_driver.cc
-@@ -167,6 +167,7 @@ CompilerInstance* CreateCompilerInstance(int argc, const char **argv) {
-   DiagnosticsEngine diagnostics(diagnostic_id, &*diagnostic_options,
-                                 diagnostic_client);
-   Driver driver(path, getDefaultTargetTriple(), diagnostics);
+@@ -249,6 +249,7 @@ bool ExecuteAction(int argc, const char** argv,
+                                           /*CodeGenOpts=*/nullptr);
+
+   Driver driver(path, getDefaultTargetTriple(), *diagnostics);
 +  driver.ResourceDir = "/usr/lib64/clang/$llvm_full_version";
    driver.setTitle("include what you use");