trees: avoid kconfig make commands generically

don't hardcode the check based on whether the current
project is grub. instead, define "btype" in target.cfg

if unset, we assume kconfig and permit kconfig commands
e.g. make menuconfig, make silentoldconfig, etc

this is to avoid the deadliest of sins:
project-specific hacks

Signed-off-by: Leah Rowe <leah@libreboot.org>

config/grub/default/target.cfg

@@ -3,3 +3,4 @@ rev="8719cc2040368d43ab2de0b6e1b850b2c9cfc5b7"
 bootstrapargs="--gnulib-srcdir=gnulib/ --no-git"
 autoconfargs="--with-platform=coreboot --disable-werror"
 makeargs="FS_PAYLOAD_MODULES=\"\""
+btype="autohell"

config/grub/nvme/target.cfg

@@ -3,3 +3,4 @@ rev="8719cc2040368d43ab2de0b6e1b850b2c9cfc5b7"
 bootstrapargs="--gnulib-srcdir=gnulib/ --no-git"
 autoconfargs="--with-platform=coreboot --disable-werror"
 makeargs="FS_PAYLOAD_MODULES=\"\""
+btype="autohell"

config/grub/xhci/target.cfg

@@ -3,3 +3,4 @@ rev="8719cc2040368d43ab2de0b6e1b850b2c9cfc5b7"
 bootstrapargs="--gnulib-srcdir=gnulib/ --no-git"
 autoconfargs="--with-platform=coreboot --disable-werror"
 makeargs="FS_PAYLOAD_MODULES=\"\""
+btype="autohell"

config/uefitool/target.cfg

@@ -1 +1,2 @@
 cmakedir="UEFIExtract"
+btype="cmake"

script/trees

@@ -11,8 +11,8 @@ set -u -e
 
 cbmakeargs="UPDATED_SUBMODULES=1 CPUS=$XBMK_THREADS"
 eval `setvars "" xarch cdir config config_name xlang mode makeargs \
-    listfile project target target_dir targets tree _f target1 bootstrapargs \
-    autoconfargs cmakedir elfdir autogenargs xtree`
+    elfdir project target target_dir targets tree _f target1 bootstrapargs \
+    autoconfargs cmakedir listfile autogenargs xtree btype`
 
 main()
 {
@@ -63,7 +63,7 @@ build_projects()
 		fetch_project_repo; return 0
 	fi
 
-	load_project_config "$cfgsdir"
+	load_project_config "$cfgsdir" || return 0
 	[ -f "$listfile" ] || listfile="" # optional on single-tree
 
 	dest_dir="$elfdir"
@@ -131,7 +131,7 @@ handle_src_tree()
 		fetch_project_trees; return 1
 	fi
 
-	load_project_config "$target_dir"
+	load_project_config "$target_dir" || return 1
 	x_ mkdir -p "$elfdir/$target"
 
 	chkvars tree
@@ -153,8 +153,10 @@ handle_src_tree()
 load_project_config()
 {
 	eval `setvars "" xarch xlang tree bootstrapargs autoconfargs xtree \
-	    tree_depend makeargs`
-	eval `setcfg "$1/target.cfg" 0`; return 0
+	    tree_depend makeargs btype`
+	eval `setcfg "$1/target.cfg" 0`
+	[ -z "$btype" ] || [ "${mode%config}" = "$mode" ] || \
+	    return 1; return 0
 }
 
 check_cross_compiler()
@@ -213,11 +215,9 @@ elfcheck()
 
 handle_makefile()
 {
-	[ "$project" = "grub" ] && [ "${mode%config}" != "$mode" ] && return 0
-
 	check_makefile "$cdir" && x_ make clean -C "$cdir"
 	x_ cp "$config" "$cdir/.config"
-	[ -n "$mode" ] || [ "$project" = "grub" ] || make -C "$cdir" \
+	[ -n "$mode" ] || [ -n "$btype" ] || make -C "$cdir" \
 	    silentoldconfig || make -C "$cdir" oldconfig || :
 
 	run_make_command || $err "handle_makefile $cdir: no makefile!"