Add test for multilib installation

Make sure that llvm-devel and llvm-devel.i686 can be installed
at the same time.

tests/multilib-install/main.fmf

@@ -0,0 +1,26 @@
+summary: Make sure that multilib installation works
+tier: 1
+
+require+:
+  - llvm-devel
+  - llvm-devel.i686
+
+link:
+  - verifies: https://bugzilla.redhat.com/show_bug.cgi?id=2365079
+
+adjust+:
+  - enabled: false
+    because: "Test applicable only on x86_64 arch"
+    when: arch != x86_64
+
+  - enabled: false
+    because: "i686 packages may not be available in snapshot builds when x86_64 tests are executed"
+    when: snapshot is defined
+
+  - enabled: false
+    because: "compat packages are not compatible with multilib"
+    when: compat is defined
+
+  - enabled: false
+    because: "i686 not supported in RHEL-10 and newer"
+    when: distro >= rhel-10 or distro >= centos-stream-10

tests/multilib-install/test.sh

@@ -0,0 +1,5 @@
+#!/bin/sh -eux
+
+# For now just check that installation works.
+rpm -q llvm-devel.x86_64
+rpm -q llvm-devel.i686

tests/shlibs-cet-support/test.sh

@@ -2,7 +2,7 @@
 
 tmp=$(mktemp -d)
 pushd "$tmp"
-for lib in $(rpm -ql llvm-libs | grep -E '\.so(\..+)?$'); do
+for lib in $(rpm -ql llvm-libs.x86_64 | grep -E '\.so(\..+)?$'); do
     [[ -L $lib ]] && continue # Skip symlinks
     readelf -n "$lib" > notes.log
     grep -q "SHSTK" notes.log