Add checks for gcc/clang with LTO

.github/workflows/compilers.yml

@@ -55,6 +55,11 @@ jobs:
           - { key: default_cc, name: gcc-6,     value: gcc-6,     container: gcc-6 }
           - { key: default_cc, name: gcc-5,     value: gcc-5,     container: gcc-5 }
           - { key: default_cc, name: gcc-4.8,   value: gcc-4.8,   container: gcc-4.8 }
+          - key: default_cc
+            name: 'gcc-11 LTO'
+            value: 'gcc-11 -O2 -flto=auto -ffat-lto-objects'
+            container: gcc-11
+            check: true
           - { key: default_cc, name: clang-14,  value: clang-14,  container: clang-14 }
           - { key: default_cc, name: clang-13,  value: clang-13,  container: clang-13 }
           - { key: default_cc, name: clang-12,  value: clang-12,  container: clang-12 }
@@ -67,6 +72,11 @@ jobs:
           - { key: default_cc, name: clang-5.0, value: clang-5.0, container: clang-5.0 }
           - { key: default_cc, name: clang-4.0, value: clang-4.0, container: clang-4.0 }
           - { key: default_cc, name: clang-3.9, value: clang-3.9, container: clang-3.9 }
+          - key: default_cc
+            name: 'clang-14 LTO'
+            value: 'clang-14 -O2 -flto=auto'
+            container: clang-14
+            check: true
 
           - { key: crosshost, name: aarch64-linux-gnu,     value: aarch64-linux-gnu, container: crossbuild-essential-arm64 }
 #         - { key: crosshost, name: arm-linux-gnueabi,     value: arm-linux-gnueabi }