riscv: t-head: licheepi4a: initial support added

Add support for Sipeed's Lichee Pi 4A board which based on T-HEAD's
TH1520 SoC, only minimal device tree and serial console are enabled,
so it's capable of chain booting from T-HEAD's vendor u-boot.

Reviewed-by: Wei Fu <wefu@redhat.com>
Signed-off-by: Yixun Lan <dlan@gentoo.org>
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index de7d5a9..867cbcb 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -27,6 +27,10 @@
 config TARGET_STARFIVE_VISIONFIVE2
 	bool "Support StarFive VisionFive2 Board"
 
+config TARGET_TH1520_LPI4A
+	bool "Support Sipeed's TH1520 Lichee PI 4A Board"
+	select SYS_CACHE_SHIFT_6
+
 config TARGET_SIPEED_MAIX
 	bool "Support Sipeed Maix Board"
 	select SYS_CACHE_SHIFT_6
@@ -66,6 +70,7 @@
 source "board/microchip/mpfs_icicle/Kconfig"
 source "board/sifive/unleashed/Kconfig"
 source "board/sifive/unmatched/Kconfig"
+source "board/thead/th1520_lpi4a/Kconfig"
 source "board/openpiton/riscv64/Kconfig"
 source "board/sipeed/maix/Kconfig"
 source "board/starfive/visionfive2/Kconfig"