board: starfive: Rename spl_soc_init() to spl_dram_init()

Rename spl_soc_init() to spl_dram_init() because the generic function
name does not reflect what the function actually does. Also
spl_dram_init() is commonly used for dram initialization and should be
called from board_init_f().

Signed-off-by: Lukas Funke <lukas.funke@weidmueller.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/arch/riscv/cpu/jh7110/spl.c b/arch/riscv/cpu/jh7110/spl.c
index 6bdf8b9..87aaf86 100644
--- a/arch/riscv/cpu/jh7110/spl.c
+++ b/arch/riscv/cpu/jh7110/spl.c
@@ -28,7 +28,7 @@
 	}
 }
 
-int spl_soc_init(void)
+int spl_dram_init(void)
 {
 	int ret;
 	struct udevice *dev;