x86/dumpstack: Avoid uninitlized variable

x86/dumpstack: Avoid uninitlized variable

BugLink: http://bugs.launchpad.net/bugs/1774063
[ Upstream commit ebfc15019cfa72496c674ffcb0b8ef10790dcddc ]

In some configurations, 'partial' does not get initialized, as shown by
this gcc-8 warning:

arch/x86/kernel/dumpstack.c: In function 'show_trace_log_lvl':
arch/x86/kernel/dumpstack.c:156:4: error: 'partial' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    show_regs_if_on_stack(&stack_info, regs, partial);
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This initializes it to false, to get the previous behavior in this case.

Fixes: a9cdbe72c4e8 ("x86/dumpstack: Fix partial register dumps")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: https://lkml.kernel.org/r/20180202145634.200291-1-arnd@arndb.de
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>