Turn off safeseh for lld.

Because lld has safeseh enabled by default and fails with a special
icu data object file icudt69l_dat.obj.

This fixes the X86 build.

Author: hjyamauchi

build.ps1

@@ -429,6 +429,10 @@ function Build-CMakeProject
     $SwiftArgs.Add("-Xlinker /INCREMENTAL:NO") | Out-Null
     $SwiftArgs.Add("-Xlinker /DEBUG:DWARF") | Out-Null
 
+    # Turn off safeseh for lld as it has safeseh enabled by default
+    # and fails with an ICU data object file icudt69l_dat.obj.
+    $SwiftArgs.Add("-Xlinker /SAFESEH:NO") | Out-Null
+
     # Swift Requries COMDAT folding and de-duplication
     $SwiftArgs.Add("-Xlinker /OPT:REF") | Out-Null
     $SwiftArgs.Add("-Xlinker /OPT:ICF") | Out-Null