drivers: st: uart: remove old API

Now that MULTI_CONSOLE_API is enabled for the STM32MP1 platform,
we can remove the non MULTI_CONSOLE_API parts in the driver.
Signed-off-by: Yann Gautier <yann.gautier@st.com>

drivers/st/uart/aarch32/stm32_console.S

@@ -87,7 +87,6 @@ core_init_fail:
 	bx	lr
 endfunc console_stm32_core_init
 
-#if MULTI_CONSOLE_API
 	.globl console_stm32_register
 
 	/* -------------------------------------------------------
@@ -123,16 +122,6 @@ func console_stm32_register
 register_fail:
 	pop	{r4, pc}
 endfunc console_stm32_register
-#else
-	.globl console_core_init
-	.globl console_core_putc
-	.globl console_core_getc
-	.globl console_core_flush
-	.equ console_core_init, console_stm32_core_init
-	.equ console_core_putc, console_stm32_core_putc
-	.equ console_core_getc, console_stm32_core_getc
-	.equ console_core_flush, console_stm32_core_flush
-#endif
 
 	/* ---------------------------------------------------------------
 	 * int console_core_putc(int c, uintptr_t base_addr)