Revert "kaleidoscope-builder: Allow easily selecting a compiler"

This reverts commit 56a729260f.

etc/kaleidoscope-builder.conf

@@ -35,23 +35,6 @@ if [ -z "${FQBN}" ]; then
    FQBN="${FQBN:-keyboardio:avr:${BOARD}}"
 fi
 
-if [ ! -z "${KALEIDOSCOPE_COMPILER}" ]; then
-    case "${KALEIDOSCOPE_COMPILER}" in
-        gnu|gcc|g++)
-            C_COMPILER_BASENAME=gcc
-            CXX_COMPILER_BASENAME=g++
-            ;;
-        clang)
-            C_COMPILER_BASENAME=clang
-            CXX_COMPILER_BASENAME=clang++
-            ;;
-        *)
-            echo "Unsupported compiler: ${KALEIDOSCOPE_COMPILER}" >&2
-            exit 1
-            ;;
-    esac
-fi
-
 ########
 ######## Host OS specific commands
 ########