libspdm: skip unsupported architectures instead of erroring

Change bb.error to bb.parse.SkipRecipe so the recipe is skipped at parse
time for unsupported architectures, rather than raising a fatal error
that breaks parsing even when the recipe is not in use.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

meta-oe/recipes-support/libspdm/libspdm_3.8.2.bb

@@ -43,7 +43,7 @@ def get_spdm_multiarch(bb, d):
     if target_arch in multiarch_options :
         return multiarch_options[target_arch]
 
-    bb.error("unsupported architecture '%s'" % target_arch)
+    raise bb.parse.SkipRecipe("unsupported architecture '%s'" % target_arch)
 
 EXTRA_OECMAKE += "\
     -DARCH=${@get_spdm_multiarch(bb, d)} \