meta-google: sysctl: set pid_max to 32k

This is already the default for 32-bit machines. Reduce it on 64-bit
machines to limit the range of PIDs that will be handled by our metrics
collector.

Signed-off-by: Benjamin Fair <benjaminfair@google.com>
Change-Id: I209317df2574b335e9e435d8b0ff1faef31ffcc3
diff --git a/meta-google/recipes-google/systemd/files/40-gbmc-sysctl.conf b/meta-google/recipes-google/systemd/files/40-gbmc-sysctl.conf
index ee4b485..5b3fa9e 100644
--- a/meta-google/recipes-google/systemd/files/40-gbmc-sysctl.conf
+++ b/meta-google/recipes-google/systemd/files/40-gbmc-sysctl.conf
@@ -1 +1,3 @@
 kernel.oops_all_cpu_backtrace = 1
+# limit PID numbers to 32k for metrics collector
+kernel.pid_max = 32768