Merge patch "RISC-V: fix incorrect type of ARCH_CANAAN_K210_DTB_SOURCE"

This fixes an issue with the K210 Kconfig cleanups, I'm just merging it
from that to avoid crossing the streams.

* b4-shazam-merge:
  RISC-V: fix incorrect type of ARCH_CANAAN_K210_DTB_SOURCE

Link: https://lore.kernel.org/r/20230111104848.2088516-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/Kconfig.socs

@@ -79,7 +79,8 @@ config SOC_CANAAN_K210_DTB_BUILTIN
 	  If unsure, say Y.
 
 config ARCH_CANAAN_K210_DTB_SOURCE
-	def_bool SOC_CANAAN_K210_DTB_SOURCE
+	string
+	default SOC_CANAAN_K210_DTB_SOURCE
 
 config SOC_CANAAN_K210_DTB_SOURCE
 	string "Source file for the Canaan Kendryte K210 builtin DTB"