Makefile: use IO_USB_MAX_ENDPOINTS=4

The default value used in Makefile.standard_app

Makefile

@@ -60,8 +60,6 @@ show-app:
 
 DISABLE_STANDARD_APP_SYNC_RAPDU = 1
 DISABLE_STANDARD_APP_FILES = 1
-DISABLE_STANDARD_USB = 1
-DEFINES   += HAVE_IO_USB HAVE_L4_USBLIB IO_USB_MAX_ENDPOINTS=6 IO_HID_EP_LENGTH=64 HAVE_USB_APDU
 DEFINES   += HAVE_LEGACY_PID
 DEFINES   += VERSION=\"$(APPVERSION)\" APPVERSION_M=$(APPVERSION_M)
 DEFINES   += COMMIT=\"$(COMMIT)\" APPVERSION_N=$(APPVERSION_N) APPVERSION_P=$(APPVERSION_P)
@@ -91,7 +89,6 @@ CFLAGS   += -Wno-incompatible-pointer-types-discards-qualifiers
 
 ### computed variables
 APP_SOURCE_PATH  += src
-SDK_SOURCE_PATH  += lib_stusb lib_stusb_impl
 
 VARIANT_PARAM  = APP
 VARIANT_VALUES = tezos_baking