package/python-ujson: fix arc build

Fix the follownig build failure on arc since bump to version 4.1.0 in
commit a47f332a20bf3f79ef4903c8ddd2b7917217e354 and
https://github.com/ultrajson/ultrajson/commit/eb7d894f225bb89d269188ba6ec559b914a71b8a:

In file included from ./deps/double-conversion/double-conversion/bignum-dtoa.h:31,
                 from ./deps/double-conversion/double-conversion/bignum-dtoa.cc:30:
./deps/double-conversion/double-conversion/utils.h:92:2: error: #error Target architecture was not detected as supported by Double-Conversion.
   92 | #error Target architecture was not detected as supported by Double-Conversion.
      |  ^~~~~

Fixes:
 - http://autobuild.buildroot.org/results/93f231c4a860f4467029a2c2e4fc0b67096b14f6

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/python-ujson/0002-Add-support-of-ARC-architecture.patch

@@ -0,0 +1,36 @@
+From eafa625a34fd5d8bec18eddfccbca55ce77b4849 Mon Sep 17 00:00:00 2001
+From: Alexey Brodkin <abrodkin@synopsys.com>
+Date: Thu, 1 Nov 2018 17:36:17 +0200
+Subject: [PATCH] Add support of ARC architecture (#82)
+
+More info about ARC architecture is here: [1] & [2].
+We need ARC supported here for many things like:
+ - ICU (see [3])
+ - Qt5 etc
+
+[1] https://www.synopsys.com/designware-ip/processor-solutions/arc-processors.html
+[2] https://en.wikipedia.org/wiki/ARC_(processor)
+[3] https://unicode-org.atlassian.net/browse/ICU-20155
+
+Fixes #81
+
+[Retrieved from:
+https://github.com/google/double-conversion/commit/eafa625a34fd5d8bec18eddfccbca55ce77b4849]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ double-conversion/utils.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/deps/double-conversion/double-conversion/utils.h b/deps/double-conversion/double-conversion/utils.h
+index 41c5b02..2e1be0d 100644
+--- a/deps/double-conversion/double-conversion/utils.h
++++ b/deps/double-conversion/double-conversion/utils.h
+@@ -94,7 +94,7 @@ int main(int argc, char** argv) {
+     defined(_MIPS_ARCH_MIPS32R2) || \
+     defined(__AARCH64EL__) || defined(__aarch64__) || defined(__AARCH64EB__) || \
+     defined(__riscv) || \
+-    defined(__or1k__)
++    defined(__or1k__) || defined(__arc__)
+ #define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1
+ #elif defined(__mc68000__) || \
+     defined(__pnacl__) || defined(__native_client__)