bootloader: Allow 'silent assert' config to work in bootloader

Requires adding the 'newlib' component to the bootloader project, for
platform_include header.

components/bootloader/subproject/CMakeLists.txt

@@ -28,10 +28,11 @@ set(COMPONENTS
     micro-ecc
     main
     efuse
-    esp_system)
+    esp_system
+    newlib)
 set(BOOTLOADER_BUILD 1)
 include("${IDF_PATH}/tools/cmake/project.cmake")
-set(common_req log esp_rom esp_common esp_hw_support hal)
+set(common_req log esp_rom esp_common esp_hw_support hal newlib)
 if(LEGACY_INCLUDE_COMMON_HEADERS)
     list(APPEND common_req soc hal)
 endif()

components/newlib/CMakeLists.txt

@@ -1,3 +1,9 @@
+if(BOOTLOADER_BUILD)
+    # Bootloader builds need the platform_include directory (for assert.h), but nothing else
+    idf_component_register(INCLUDE_DIRS platform_include)
+    return()
+endif()
+
 set(srcs
     "abort.c"
     "heap.c"