bootloader: Add bootloader Kconfig

Allow debug level & colour highlighting to be configured

components/bootloader/Kconfig.projbuild

@@ -0,0 +1,33 @@
+menu "Bootloader config"
+
+choice BOOTLOADER_LOG_LEVEL
+   bool "Bootloader log verbosity"
+   default BOOTLOADER_LOG_LEVEL_NOTICE
+   help
+       Specify how much output to see in the bootloader logs.
+
+       Note that if MTDO is HIGH on reset, all early boot output
+       (including bootloader logs) are suppressed.
+config BOOTLOADER_LOG_LEVEL_NONE
+   bool "No output"
+config BOOTLOADER_LOG_LEVEL_ERROR
+   bool "Error"
+config BOOTLOADER_LOG_LEVEL_WARN
+   bool "Warning"
+config BOOTLOADER_LOG_LEVEL_INFO
+   bool "Info"
+config BOOTLOADER_LOG_LEVEL_NOTICE
+   bool "Notice"
+config BOOTLOADER_LOG_LEVEL_DEBUG
+   bool "Debug"
+endchoice
+
+config BOOTLOADER_LOG_COLORS
+   bool "Use ANSI terminal colors in bootloader log output"
+   default "y"
+   help
+      Enable ANSI terminal color codes in bootloader output.
+
+      In order to view these, your terminal program must support ANSI color codes.
+
+endmenu