Remove converter assumption that everything is a promicro (#20330)

builddefs/converters.mk

@@ -1,8 +1,3 @@
-ifneq (,$(filter $(MCU),atmega32u4))
-    # TODO: opt in rather than assume everything uses a pro micro
-    PIN_COMPATIBLE ?= promicro
-endif
-
 # Remove whitespace from any rule.mk provided vars
 #   - env cannot be overwritten but cannot have whitespace anyway
 CONVERT_TO:=$(strip $(CONVERT_TO))