s7: add_syslinks m (#2293)

packages/s/s7/port/xmake.lua

@@ -40,6 +40,6 @@ target("s7") do
         add_ldflags("-static", "-static-libgcc", {force = true})
     end
     if is_plat("linux") then
-        add_syslinks("pthread", "dl")
+        add_syslinks("pthread", "dl", "m")
     end
 end

packages/s/s7/xmake.lua

@@ -18,7 +18,7 @@ package("s7")
     end)
 
     if is_plat("linux") then
-        add_syslinks("pthread", "dl")
+        add_syslinks("pthread", "dl", "m")
     end
 
     on_install("bsd", "cross", "cygwin", "linux", "macosx", "mingw", "msys", "wasm", "windows", function (package)