lgtm.yml: Delete.

"LGTM" code scanning was bought out and merged into GitHub Actions.
The code scanning setup there has a different mechanism for configuration,
and so this file is not useful anymore.

lgtm.yml

@@ -1,36 +0,0 @@
-extraction:
-  cpp:
-    prepare:
-      packages:
-        - git
-        - nasm
-        - autoconf
-        - automake
-        - texinfo
-        - flex
-        - bison
-        - gawk
-        - build-essential
-        - unzip
-        - wget
-        - zip
-        - less
-        - zlib1g-dev
-        - libzstd-dev
-        - xorriso
-        - libtool
-        - gcc-multilib
-        - python3
-    after_prepare:
-      - curl https://codeload.github.com/haiku/buildtools/zip/master -o master.zip
-      - mkdir $LGTM_WORKSPACE/buildtools
-      - unzip -qq master.zip -d $LGTM_WORKSPACE/buildtools
-      - rm master.zip
-      - cd $LGTM_WORKSPACE/buildtools/buildtools-master/jam && make && BINDIR=$LGTM_WORKSPACE/bin ./jam0 install
-    configure:
-      command:
-        - acx_cv_prog_cc_warning__Werror_format_diag=no ./configure --cross-tools-source $LGTM_WORKSPACE/buildtools/buildtools-master --build-cross-tools x86_64 --use-gcc-pipe -j2
-    index:
-      build_command:
-        - HAIKU_REVISION=hrev90000 $LGTM_WORKSPACE/bin/jam -j2 @nightly-raw
-