dt-bindings: clock: remove unused definition for stm32mp1

A copy of LTDC_PX and ETHCK_K (LTDC_K and ETHMAC_K) was introduced in
stm32mp1 dt-bindings file by mistake.
These bindings are not used and shouldn't be use to be conform with
convention name of the stm32mp1 clock IP.
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

include/dt-bindings/clock/stm32mp1-clks.h

@@ -248,7 +248,4 @@
 
 #define STM32MP1_LAST_CLK 232
 
-#define LTDC_K		LTDC_PX
-#define ETHMAC_K	ETHCK_K
-
 #endif /* _DT_BINDINGS_STM32MP1_CLKS_H_ */