extmod/modmachine: Consolidate simple machine headers into modmachine.h.

The contents of machine_bitstream.h, machine_pinbase.h, machine_pulse.h and
machine_signal.h have been moved into extmod/modmachine.h.

Signed-off-by: Damien George <damien@micropython.org>

ports/esp8266/modmachine.c

@@ -36,10 +36,7 @@
 // This needs to be set before we include the RTOS headers
 #define USE_US_TIMER 1
 
-#include "extmod/machine_bitstream.h"
 #include "extmod/machine_mem.h"
-#include "extmod/machine_signal.h"
-#include "extmod/machine_pulse.h"
 #include "extmod/machine_i2c.h"
 #include "extmod/machine_spi.h"
 #include "extmod/modmachine.h"

ports/esp8266/modos.c

@@ -35,7 +35,6 @@
 #include "extmod/vfs_fat.h"
 #include "extmod/vfs_lfs.h"
 #include "genhdr/mpversion.h"
-#include "esp_mphal.h"
 #include "user_interface.h"
 
 STATIC const char *mp_os_uname_release(void) {