Documentation: Add nospectre_v1 parameter

commit 26cb1f36 upstream.

Currently only supported on powerpc.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/kernel-parameters.txt

@@ -2758,6 +2758,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	nohugeiomap	[KNL,x86] Disable kernel huge I/O mappings.
 
+	nospectre_v1	[PPC] Disable mitigations for Spectre Variant 1 (bounds
+			check bypass). With this option data leaks are possible
+			in the system.
+
 	nosmt		[KNL,S390] Disable symmetric multithreading (SMT).
 			Equivalent to smt=1.