[Keyboard] Remove relative location of i2c master/slave as it causes the build to write to a folder outside of qmk_firmware (#6039)

keyboards/dc01/arrow/rules.mk

@@ -1,5 +1,5 @@
 SRC += matrix.c \
-       ../../../drivers/avr/i2c_slave.c
+       i2c_slave.c
 
 # MCU name
 #MCU = at90usb1286

keyboards/dc01/left/rules.mk

@@ -1,5 +1,5 @@
 SRC += matrix.c \
-      ../../../drivers/avr/i2c_master.c
+       i2c_master.c
 
 # MCU name
 #MCU = at90usb1286

keyboards/dc01/numpad/rules.mk

@@ -1,5 +1,5 @@
 SRC += matrix.c \
-       ../../../drivers/avr/i2c_slave.c
+       i2c_slave.c
 
 # MCU name
 #MCU = at90usb1286

keyboards/dc01/right/rules.mk

@@ -1,5 +1,5 @@
 SRC += matrix.c \
-       ../../../drivers/avr/i2c_slave.c
+       i2c_slave.c
 
 # MCU name
 #MCU = at90usb1286