mesa: Fix build on 32bit arches supporting 64bit time_t only

Fixes
../mesa-20.1.8/src/util/futex.h:47:19: error: use of undeclared identifier 'SYS_futex'; did you mean 'sys_futex'?
   return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3);
                  ^~~~~~~~~
                  sys_futex

(From OE-Core rev: 21bdff510a7673ccf7f27f551b641a5ba84d656c)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-graphics/mesa/files/0001-futex.h-Define-__NR_futex-if-it-does-not-exist.patch

@@ -0,0 +1,31 @@
+From 8973e297f2f9b17498b9dc0e37a19481d4bb7df9 Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Fri, 16 Oct 2020 11:03:47 -0700
+Subject: [PATCH] futex.h: Define __NR_futex if it does not exist
+
+__NR_futex is not defines by newer architectures e.g. arc, riscv32 as
+they only have 64bit variant of time_t. Glibc defines SYS_futex interface based on
+__NR_futex, since this is used in applications, such applications start
+to fail to build for these newer architectures. This patch defines a
+fallback to alias __NR_futex to __NR_futex_tim64 so SYS_futex keeps
+working
+
+Upstream-Status: Pending
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ src/util/futex.h | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+--- a/src/util/futex.h
++++ b/src/util/futex.h
+@@ -34,6 +34,10 @@
+ #include <sys/syscall.h>
+ #include <sys/time.h>
+ 
++#if !defined(SYS_futex) && defined(SYS_futex_time64)
++# define SYS_futex SYS_futex_time64
++#endif
++
+ static inline long sys_futex(void *addr1, int op, int val1, const struct timespec *timeout, void *addr2, int val3)
+ {
+    return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3);

meta/recipes-graphics/mesa/mesa.inc

@@ -21,6 +21,7 @@ SRC_URI = "https://mesa.freedesktop.org/archive/mesa-${PV}.tar.xz \
            file://0004-Revert-mesa-Enable-asm-unconditionally-now-that-gen_.patch \
            file://0005-vc4-use-intmax_t-for-formatted-output-of-timespec-me.patch \
            file://0001-meson-misdetects-64bit-atomics-on-mips-clang.patch \
+           file://0001-futex.h-Define-__NR_futex-if-it-does-not-exist.patch \
            "
 
 SRC_URI[sha256sum] = "df21351494f7caaec5a3ccc16f14f15512e98d2ecde178bba1d134edc899b961"