[PATCH] powerpc: Fix missing prototype problems for "arch/powerpc/kernel/setup_64.c"

[He Ying <heying24@huawei.com>]

The variables 'uaccess_fulsh' and 'entry_flush' are not referenced
outside the file. So define them as static to avoid the warnings.

And add a prototype for the function 'panic_smp_self_stop' for the
same purpose.

Sparse also warns that 'rfi_flush' should be static. However, it's
referenced outside the file.

The warnings about the file reported by sparse are as follows:
arch/powerpc/kernel/setup_64.c:422:6: warning: symbol 'panic_smp_self_stop' was not declared. Should it be static?
arch/powerpc/kernel/setup_64.c:951:6: warning: symbol 'rfi_flush' was not declared. Should it be static?
arch/powerpc/kernel/setup_64.c:952:6: warning: symbol 'entry_flush' was not declared. Should it be static?
arch/powerpc/kernel/setup_64.c:953:6: warning: symbol 'uaccess_flush' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
---
 arch/powerpc/kernel/setup_64.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 560ed8b975e7..603aacd8527b 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -71,6 +71,8 @@
 
 #include "setup.h"
 
+extern void panic_smp_self_stop(void);
+
 int spinning_secondaries;
 u64 ppc64_pft_size;
 
@@ -949,8 +951,8 @@ static bool no_rfi_flush;
 static bool no_entry_flush;
 static bool no_uaccess_flush;
 bool rfi_flush;
-bool entry_flush;
-bool uaccess_flush;
+static bool entry_flush;
+static bool uaccess_flush;
 DEFINE_STATIC_KEY_FALSE(uaccess_flush_key);
 EXPORT_SYMBOL(uaccess_flush_key);
 
-- 
2.17.1