Fix disabling of FRAMEBUFFERIO on atmel-samd

.. this needs to imply the disabling of RGBMATRIX too

Author: jepler

ports/atmel-samd/mpconfigport.mk

@@ -103,8 +103,8 @@ CIRCUITPY_TOUCHIO_USE_NATIVE = 0
 CIRCUITPY_ALARM ?= 0
 CIRCUITPY_PS2IO ?= 1
 CIRCUITPY_SAMD ?= 1
-CIRCUITPY_RGBMATRIX ?= $(CIRCUITPY_FULL_BUILD)
 CIRCUITPY_FRAMEBUFFERIO ?= $(CIRCUITPY_FULL_BUILD)
+CIRCUITPY_RGBMATRIX ?= $(CIRCUITPY_FRAMEBUFFERIO)
 CIRCUITPY_WATCHDOG ?= 1
 
 endif # samd51
@@ -122,8 +122,8 @@ CIRCUITPY_TOUCHIO_USE_NATIVE = 0
 
 CIRCUITPY_PS2IO ?= 1
 CIRCUITPY_SAMD ?= 1
-CIRCUITPY_RGBMATRIX ?= $(CIRCUITPY_FULL_BUILD)
 CIRCUITPY_FRAMEBUFFERIO ?= $(CIRCUITPY_FULL_BUILD)
+CIRCUITPY_RGBMATRIX ?= $(CIRCUITPY_FRAMEBUFFERIO)
 
 endif # same51
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