Update config.sub and config.guess for MIPS R3 and R5 ISA support

Complement commit ae52f48306 ("Add MIPS r3 and r5 support.") and get
changes for config.sub to recognize MIPS CPU patterns for the R3 and R5
ISA levels, used by GAS to set defaults in gas/configure.ac.  Oddly, R6
ISA support has been correctly added already.

	/
	* config.guess: Import from upstream.
	* config.sub: Likewise.

	readline/
	* readline/support/config.guess: Import from upstream.
	* readline/support/config.sub: Likewise.

config.sub

@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2021 Free Software Foundation, Inc.
 
-timestamp='2021-01-07'
+timestamp='2021-04-30'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -1165,7 +1165,7 @@ case $cpu-$vendor in
 			| alphapca5[67] | alpha64pca5[67] \
 			| am33_2.0 \
 			| amdgcn \
-			| arc | arceb \
+			| arc | arceb | arc64 \
 			| arm | arm[lb]e | arme[lb] | armv* \
 			| avr | avr32 \
 			| asmjs \
@@ -1204,9 +1204,13 @@ case $cpu-$vendor in
 			| mips64vr5900 | mips64vr5900el \
 			| mipsisa32 | mipsisa32el \
 			| mipsisa32r2 | mipsisa32r2el \
+			| mipsisa32r3 | mipsisa32r3el \
+			| mipsisa32r5 | mipsisa32r5el \
 			| mipsisa32r6 | mipsisa32r6el \
 			| mipsisa64 | mipsisa64el \
 			| mipsisa64r2 | mipsisa64r2el \
+			| mipsisa64r3 | mipsisa64r3el \
+			| mipsisa64r5 | mipsisa64r5el \
 			| mipsisa64r6 | mipsisa64r6el \
 			| mipsisa64sb1 | mipsisa64sb1el \
 			| mipsisa64sr71k | mipsisa64sr71kel \
@@ -1683,12 +1687,15 @@ fi
 
 # Now, validate our (potentially fixed-up) OS.
 case $os in
-	# Sometimes we do "kernel-abi", so those need to count as OSes.
+	# Sometimes we do "kernel-libc", so those need to count as OSes.
 	musl* | newlib* | uclibc*)
 		;;
-	# Likewise for "kernel-libc"
+	# Likewise for "kernel-abi"
 	eabi* | gnueabi*)
 		;;
+	# VxWorks passes extra cpu info in the 4th filed.
+	simlinux | simwindows | spe)
+		;;
 	# Now accept the basic system types.
 	# The portable systems comes first.
 	# Each alternative MUST end in a * to match a version number.
@@ -1704,12 +1711,12 @@ case $os in
 	     | nindy* | vxsim* | vxworks* | ebmon* | hms* | mvs* \
 	     | clix* | riscos* | uniplus* | iris* | isc* | rtu* | xenix* \
 	     | mirbsd* | netbsd* | dicos* | openedition* | ose* \
-	     | bitrig* | openbsd* | solidbsd* | libertybsd* | os108* \
+	     | bitrig* | openbsd* | secbsd* | solidbsd* | libertybsd* | os108* \
 	     | ekkobsd* | freebsd* | riscix* | lynxos* | os400* \
 	     | bosx* | nextstep* | cxux* | aout* | elf* | oabi* \
 	     | ptx* | coff* | ecoff* | winnt* | domain* | vsta* \
 	     | udi* | lites* | ieee* | go32* | aux* | hcos* \
-	     | chorusrdb* | cegcc* | glidix* \
+	     | chorusrdb* | cegcc* | glidix* | serenity* \
 	     | cygwin* | msys* | pe* | moss* | proelf* | rtems* \
 	     | midipix* | mingw32* | mingw64* | mint* \
 	     | uxpv* | beos* | mpeix* | udk* | moxiebox* \
@@ -1751,6 +1758,8 @@ case $kernel-$os in
 		;;
 	kfreebsd*-gnu* | kopensolaris*-gnu*)
 		;;
+	vxworks-simlinux | vxworks-simwindows | vxworks-spe)
+		;;
 	nto-qnx*)
 		;;
 	os2-emx)