boot: bootutil: remove unused BOOT_LOG_LEVEL macros

Remove unnused BOOT_LOG_LEVEL macros.
These are not honored, nor usable since they are supposed to be
defined before including the header in which they are defined.

Signed-off-by: Emanuele Di Santo <emdi@nordicsemi.no>
diff --git a/boot/bootutil/include/bootutil/bootutil_log.h b/boot/bootutil/include/bootutil/bootutil_log.h
index c8a96a6..c7bb70f 100644
--- a/boot/bootutil/include/bootutil/bootutil_log.h
+++ b/boot/bootutil/include/bootutil/bootutil_log.h
@@ -28,16 +28,6 @@
 
 #ifdef MCUBOOT_HAVE_LOGGING
 
-#ifdef BOOT_LOG_LEVEL
-#define MCUBOOT_LOG_LEVEL BOOT_LOG_LEVEL
-#endif
-
-#define BOOT_LOG_LEVEL_OFF     MCUBOOT_LOG_LEVEL_OFF
-#define BOOT_LOG_LEVEL_ERROR   MCUBOOT_LOG_LEVEL_ERROR
-#define BOOT_LOG_LEVEL_WARNING MCUBOOT_LOG_LEVEL_WARNING
-#define BOOT_LOG_LEVEL_INFO    MCUBOOT_LOG_LEVEL_INFO
-#define BOOT_LOG_LEVEL_DEBUG   MCUBOOT_LOG_LEVEL_DEBUG
-
 #define BOOT_LOG_ERR(...) MCUBOOT_LOG_ERR(__VA_ARGS__)
 #define BOOT_LOG_WRN(...) MCUBOOT_LOG_WRN(__VA_ARGS__)
 #define BOOT_LOG_INF(...) MCUBOOT_LOG_INF(__VA_ARGS__)