board/intel/galileo: fix build failure with host gcc 10

Building galileo_defconfig throws error:
```
/usr/bin/ld: arch/x86/tools/relocs_64.o:(.bss+0x0): multiple definition of `per_cpu_load_addr'; arch/x86/tools/relocs_32.o:(.bss+0x0): first defined here
```

To fix this let's add an upstreamed patch[1] and add BR2_GLOBAL_PATCH_DIR
to galileo_defconfig to point to where patch is.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eeeda4cd06e828b331b15741a204ff9f5874d28d.patch

Fixes:
https://gitlab.com/ymorin/buildroot/-/jobs/2035821039

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit 9dd5382d791c3d5197b9ef401a0d103ad1457d5d)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

board/intel/galileo/patches/linux/0001-x86-relocs-Make-per_cpu_load_addr-static.patch

@@ -0,0 +1,39 @@
+From eeeda4cd06e828b331b15741a204ff9f5874d28d Mon Sep 17 00:00:00 2001
+From: Ben Hutchings <ben@decadent.org.uk>
+Date: Wed, 24 Sep 2014 13:30:12 +0100
+Subject: [PATCH] x86/relocs: Make per_cpu_load_addr static
+
+per_cpu_load_addr is only used for 64-bit relocations, but is
+declared in both configurations of relocs.c - with different
+types.  This has undefined behaviour in general.  GNU ld is
+documented to use the larger size in this case, but other tools
+may differ and some warn about this.
+
+References: https://bugs.debian.org/748577
+Reported-by: Michael Tautschnig <mt@debian.org>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+Cc: 748577@bugs.debian.org
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Link: http://lkml.kernel.org/r/1411561812.3659.23.camel@decadent.org.uk
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
+---
+ arch/x86/tools/relocs.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
+index bbb1d2259ecf..a5efb21d5228 100644
+--- a/arch/x86/tools/relocs.c
++++ b/arch/x86/tools/relocs.c
+@@ -695,7 +695,7 @@ static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
+  *
+  */
+ static int per_cpu_shndx	= -1;
+-Elf_Addr per_cpu_load_addr;
++static Elf_Addr per_cpu_load_addr;
+ 
+ static void percpu_init(void)
+ {
+-- 
+2.25.1
+

configs/galileo_defconfig

@@ -1,4 +1,5 @@
 BR2_x86_x1000=y
+BR2_GLOBAL_PATCH_DIR=board/intel/galileo/patches
 # Needed for TARGET_GRUB2
 BR2_TOOLCHAIN_BUILDROOT_WCHAR=y
 # Linux headers same as kernel, a 3.14 series