Increase stack size a bit to silence warning

ext-partition needs a slightly bigger stack.

Change-Id: Ib727cfd5b3526b18d8c7306ddb33a490bb885834
diff --git a/configure b/configure
index 8ef2895..9829c72 100755
--- a/configure
+++ b/configure
@@ -655,7 +655,7 @@
         check_add_cflags -Wunused
         check_add_cflags -Wsign-compare
         check_add_cflags -Wlogical-op
-        check_add_cflags -Wstack-usage=307200
+        check_add_cflags -Wstack-usage=320000
         # Enabling the following warning (in combination with -Wunused above)
         # for C++ generates errors in third_party code including googletest and
         # libyuv. So enable it only for C code.