make rustc_codegen_spirv depend on rustc_codegen_spirv_target_specs for cargo gpu

Author: Firestar99

Cargo.lock

@@ -61,6 +61,9 @@ tracing.workspace = true
 tracing-subscriber.workspace = true
 tracing-tree = "0.3.0"
 
+# required for cargo gpu to resolve the needed target specs
+rustc_codegen_spirv_target_specs.workspace = true
+
 [dev-dependencies]
 pretty_assertions = "1.0"