RISC-V: Fix python3 compatibility for multilib-generator

The subprocess return string is raw bytes in python3, it must decode
before used as string, verifed with python2 and python3.

gcc/ChangeLog:

	* config/riscv/multilib-generator (arch_canonicalize): Call
	decode for the subprocess return value.

diff --git a/gcc/config/riscv/multilib-generator b/gcc/config/riscv/multilib-generator
index ccfd9ea18ea3103d0b7800d6f6db8d5f7aa55559..64ff15f449b0b92def91c18b5761c7a8f0ff4c69 100755 (executable)
--- a/gcc/config/riscv/multilib-generator
+++ b/gcc/config/riscv/multilib-generator
@@ -57,7 +57,7 @@ def arch_canonicalize(arch):
   proc = subprocess.Popen([sys.executable, arch_can_script, arch],
                           stdout=subprocess.PIPE)
   out, err = proc.communicate()
-  return out.strip()
+  return out.decode().strip()
 
 #
 # Handle expansion operation.