arm: am335x: Enable tiny printf in SPL

am335x_evm SPL is very close to its limit in SRAM space.
Switch to use tiny printf to reclaim some size.
Reviewed-by: NTom Rini <trini@konsulko.com>
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>

arch/arm/mach-omap2/Kconfig

@@ -135,6 +135,7 @@ config AM43XX
 config AM33XX
 	bool "AM33XX SoC"
 	imply SYS_THUMB_BUILD
+	imply USE_TINY_PRINTF
 	help
 	  Support for AM335x SOC from Texas Instruments.
 	  The AM335x high performance SOC features a Cortex-A8