Add plat_crash_console_flush to platforms without it

Even though at this point plat_crash_console_flush is optional, it will
stop being optional in a following patch.

The console driver of warp7 doesn't support flush, so the implementation
is a placeholder.

TI had ``plat_crash_console_init`` and ``plat_crash_console_putc``, but
they weren't global so they weren't actually used. Also, they were
calling the wrong functions.

imx8_helpers.S only has placeholders for all of the functions.

Change-Id: I8d17bbf37c7dad74e134c61ceb92acb9af497718
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/plat/imx/common/imx8_helpers.S b/plat/imx/common/imx8_helpers.S
index b89d346..19293bf 100644
--- a/plat/imx/common/imx8_helpers.S
+++ b/plat/imx/common/imx8_helpers.S
@@ -16,6 +16,7 @@
 	.globl	plat_secondary_cold_boot_setup
 	.globl	plat_crash_console_init
 	.globl	plat_crash_console_putc
+	.globl	plat_crash_console_flush
 	.globl	platform_mem_init
 	.globl  imx_mailbox_init
 
@@ -106,6 +107,7 @@
 endfunc plat_secondary_cold_boot_setup
 
 func plat_crash_console_init
+	mov	x0, #1
 	ret
 endfunc plat_crash_console_init
 
@@ -113,6 +115,11 @@
 	ret
 endfunc plat_crash_console_putc
 
+func plat_crash_console_flush
+	mov	x0, #0
+	ret
+endfunc plat_crash_console_flush
+
 func platform_mem_init
 	ret
 endfunc platform_mem_init