powerpc/fsl: Fix spectre_v2 mitigations reporting

BugLink: https://bugs.launchpad.net/bugs/1830176

commit 7d8bad99 upstream.

Currently for CONFIG_PPC_FSL_BOOK3E the spectre_v2 file is incorrect:

  $ cat /sys/devices/system/cpu/vulnerabilities/spectre_v2
  "Mitigation: Software count cache flush"

Which is wrong. Fix it to report vulnerable for now.

Fixes: ee13cb24 ("powerpc/64s: Add support for software count cache flush")
Cc: stable@vger.kernel.org # v4.19+
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>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

arch/powerpc/kernel/security.c

@@ -24,7 +24,7 @@ enum count_cache_flush_type {
 	COUNT_CACHE_FLUSH_SW	= 0x2,
 	COUNT_CACHE_FLUSH_HW	= 0x4,
 };
-static enum count_cache_flush_type count_cache_flush_type;
+static enum count_cache_flush_type count_cache_flush_type = COUNT_CACHE_FLUSH_NONE;
 
 bool barrier_nospec_enabled;
 static bool no_nospec;