kernel/ksysfs.c: expose file_caps_enabled in sysfs

A kernel booted with no_file_caps allows to install fscaps on a binary
but doesn't actually honor the fscaps when running the binary. Userspace
currently has no sane way to determine whether installing fscaps
actually has any effect. Since parsing /proc/cmdline is fragile this
patch exposes the current setting (1 or 0) via /sys/kernel/fscaps

Signed-off-by: Ludwig Nussel <ludwig.nussel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/ABI/testing/sysfs-kernel-fscaps b/Documentation/ABI/testing/sysfs-kernel-fscaps
new file mode 100644
index 0000000..50a3033
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-fscaps
@@ -0,0 +1,8 @@
+What:		/sys/kernel/fscaps
+Date:		February 2011
+KernelVersion:	2.6.38
+Contact:	Ludwig Nussel <ludwig.nussel@suse.de>
+Description
+		Shows whether file system capabilities are honored
+		when executing a binary
+