opensbi-payloads.inc: Use strings for fallback

This function is evaluated during parse and some machines maynot use
external payload, on such machines this fails to parse

Fixes
bb.data_smart.ExpansionError: Failure expanding variable do_compile[depends], expression was  ${@riscv_get_do_compile_depends(d)} which triggered exception TypeError: argument of type 'NoneType' is not iterab
le

(From OE-Core rev: b5c93cb9a63ebd8601623f411737c0af7f7efd4a)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Cc: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/meta/recipes-bsp/opensbi/opensbi-payloads.inc b/meta/recipes-bsp/opensbi/opensbi-payloads.inc
index cc31ab3b1d..ce537c0587 100644
--- a/meta/recipes-bsp/opensbi/opensbi-payloads.inc
+++ b/meta/recipes-bsp/opensbi/opensbi-payloads.inc
@@ -17,13 +17,13 @@ def riscv_get_extra_oemake_fdt(d):
     return "FW_FDT_PATH=" + deploy_dir + "/" + sbi_fdt
 
 def riscv_get_do_compile_depends(d):
-    sbi_payload = d.getVar('RISCV_SBI_PAYLOAD')
-    sbi_fdt = d.getVar('RISCV_SBI_FDT')
+    sbi_payload = d.getVar('RISCV_SBI_PAYLOAD') or ""
+    sbi_fdt = d.getVar('RISCV_SBI_FDT') or ""
 
-    if sbi_payload is None and sbi_fdt is None:
+    if sbi_payload == "" and sbi_fdt == "":
         return ""
 
-    if sbi_fdt is not None and 'u-boot.bin' in sbi_payload:
+    if sbi_fdt != "" and 'u-boot.bin' in sbi_payload:
         return "virtual/kernel:do_deploy virtual/bootloader:do_deploy"
 
     if 'linux' in sbi_payload or 'Image' in sbi_payload: