cross-gdb: Add Guile scripting support configuration

This commit adds a new configuration for enabling the GNU Guile
scripting support through the libguile.

Note that this configuration is not enabled by default because it is a
niche feature and requires the libguile, which is currently not built
by the crosstool-ng for the host (gdb also keeps this feature disabled
by default unless libguile is available for the host).

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>

config/debug/gdb.in.cross

@@ -96,6 +96,16 @@ config GDB_CROSS_LZMA
       Note that crosstool-ng does not build liblzma for the host and you are
       responsible for providing this library on the build system.
 
+config GDB_CROSS_GUILE
+    bool
+    prompt "Build GDB with GNU Guile scripting support"
+    help
+      Build GDB with libguile, a library implementing the GNU Guile scripting
+      feature.
+
+      Note that crosstool-ng does not build libguile for the host and you are
+      responsible for providing this library on the build system.
+
 config GDB_CROSS_EXTRA_CONFIG_ARRAY
     string
     prompt "Cross-gdb extra config"

scripts/build/debug/300-gdb.sh

@@ -65,6 +65,12 @@ do_debug_gdb_build_cross()
         cross_extra_config+=("--without-lzma")
     fi
 
+    if [ "${CT_GDB_CROSS_GUILE}" = "y" ]; then
+        cross_extra_config+=("--with-guile")
+    else
+        cross_extra_config+=("--without-guile")
+    fi
+
     if ${CT_HOST}-gcc --version 2>&1 | grep clang; then
         # clang detects the line from gettext's _ macro as format string
         # not being a string literal and produces a lot of warnings - which