Add blacklist to vk win intel for skp

This blacklist the desk_skbug6850overlay2 which is causing llvm to crash
on the intel win bot when running vulkan.

Bug: skia:6863
Change-Id: I2c3ca597a3312e6c0a1bacae0056fcb1c19679bf
Reviewed-on: https://skia-review.googlesource.com/24264
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>

infra/bots/recipes/perf.expected/Perf-Win10-MSVC-NUC6i5SYK-GPU-IntelIris540-x86_64-Release-Vulkan.json

@@ -178,6 +178,7 @@
       "~text_16_LCD_BK",
       "~text_16_LCD_FF",
       "~text_16_LCD_WT",
+      "~desk_skbug6850overlay2",
       "~inc0.gif",
       "~inc1.gif",
       "~incInterlaced.gif",

infra/bots/recipes/perf.py

@@ -148,6 +148,8 @@ def nanobench_flags(api, bot):
     match.append('~text_16_LCD_BK')
     match.append('~text_16_LCD_FF')
     match.append('~text_16_LCD_WT')
+    # skia:6863
+    match.append('~desk_skbug6850overlay2')
   if ('Intel' in bot and api.vars.is_linux and not 'Vulkan' in bot):
     # TODO(dogben): Track down what's causing bots to die.
     verbose = True