build: W600-SDK importiert, Firmware-Build und Hello am EVK

Docker-Build mit gcc-arm-none-eabi 4.9-2014q4 (statt Homebrew-Cask) verwendet,
Dockerfile/tools/docker.sh dafür aus Task 13 vorgezogen. cmake/sdk.cmake schont
gcc 4.9 (kennt -fcommon/-Wno-error=... nicht). Zwei zusätzliche SDK-Stubs
(EarlyInit, pre_gpio_config) in src/sys/sdk_stubs.c ergänzt, siehe sdk/PATCHES.md.

cmake/image.cmake

@@ -0,0 +1,20 @@
+# Host tool wm_tool packs the firmware into .img / _gz.img / .fls.
+set(NL_WM_TOOL ${CMAKE_BINARY_DIR}/wm_tool)
+add_custom_command(OUTPUT ${NL_WM_TOOL}
+  COMMAND cc -O2 -w -o ${NL_WM_TOOL} ${SDK_DIR}/tools/wm_tool.c -lpthread
+  DEPENDS ${SDK_DIR}/tools/wm_tool.c
+  COMMENT "Building host tool wm_tool")
+add_custom_target(nl_wm_tool DEPENDS ${NL_WM_TOOL})
+
+# 2M layout: update area 0x100000, run area 0x10100 (same as the old Klyqa images).
+function(nl_add_images target)
+  add_dependencies(${target} nl_wm_tool)
+  set(out ${CMAKE_BINARY_DIR}/${target})
+  add_custom_command(TARGET ${target} POST_BUILD
+    COMMAND ${CMAKE_OBJCOPY} --output-target=binary -S -g -x -X -R .sbss -R .bss -R .reginfo -R .stack
+            $<TARGET_FILE:${target}> ${out}.bin
+    COMMAND ${NL_WM_TOOL} -b ${out}.bin -sb ${SDK_DIR}/Bin/secboot.img -fc compress -it 2M
+            -ua 100000 -ra 10100 -df -o ${out}
+    COMMAND ${CMAKE_SIZE} $<TARGET_FILE:${target}>
+    COMMENT "Packing ${target}.fls and ${target}_gz.img")
+endfunction()