Remove include <log.h> from defines.h

The reason for this is that log.h includes drv_hrt.h which sucks in
half the project's include files with it, which causes strange build
issues

src/drivers/tap_esc/tap_esc_common.cpp

@@ -44,6 +44,7 @@
 #include <systemlib/px4_macros.h> // arraySize
 #include <px4_platform_common/px4_config.h>
 #include <px4_platform_common/defines.h>
+#include <px4_platform_common/log.h>
 
 #ifndef B250000
 #define B250000 250000