Fixes build faliure
Closes: https://bugs.gentoo.org/975037
From: https://github.com/shadps4-emu/ext-hwinfo/commit/f85127c489e0f25903d2a56d9841adb5349a86f2

--- a/externals/hwinfo/src/linux/disk.cpp
+++ b/externals/hwinfo/src/linux/disk.cpp
@@ -13,6 +13,7 @@
 #include <fstream>
 #include <regex>
 #include <vector>
+#include <sstream>
 
 namespace {