ARM: UniPhier: detect the number of flash banks at run-time

Some UniPhier boards are equipped with an expansion slot that
some optional SRAM/NOR-flash cards can be attached to.  So, run-time
detection of the number of flash banks would be more user-friendly.

Until this commit, UniPhier boards have achieved this by (ab)using
board_flash_wp_on() because the boot failed if flash_size got zero.
Fortunately, this problem was solved by commit 70879a92561a (flash:
do not fail even if flash_size is zero).

Now it is possible to throw away such a tricky workaround.  This
commit also enables CONFIG_SYS_MAX_FLASH_BANKS_DETECT for further
refactoring.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/arch/arm/cpu/armv7/uniphier/Makefile b/arch/arm/cpu/armv7/uniphier/Makefile
index 0f64d25..4a7b8a9 100644
--- a/arch/arm/cpu/armv7/uniphier/Makefile
+++ b/arch/arm/cpu/armv7/uniphier/Makefile
@@ -11,6 +11,7 @@
 obj-$(CONFIG_BOARD_POSTCLK_INIT) += board_postclk_init.o
 obj-y += dram_init.o
 obj-$(CONFIG_DISPLAY_CPUINFO) += cpu_info.o
+obj-$(CONFIG_BOARD_EARLY_INIT_R) += board_early_init_r.o
 obj-$(CONFIG_BOARD_LATE_INIT) += board_late_init.o
 obj-$(CONFIG_UNIPHIER_SMP) += smp.o
 obj-$(CONFIG_CMD_PINMON) += cmd_pinmon.o