x86/entry: Add do_SYSENTER_32() prototype

The 32-bit system call entry points can be called on both 32-bit
and 64-bit kernels, but on the former the declarations are hidden:

arch/x86/entry/common.c:238:24: error: no previous prototype for 'do_SYSENTER_32' [-Werror=missing-prototypes]

Move them all out of the #ifdef block to avoid the warnings.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/all/20230516193549.544673-12-arnd%40kernel.org

Author: arndb

arch/x86/include/asm/syscall.h

@@ -127,9 +127,11 @@ static inline int syscall_get_arch(struct task_struct *task)
 }
 
 void do_syscall_64(struct pt_regs *regs, int nr);
-void do_int80_syscall_32(struct pt_regs *regs);
-long do_fast_syscall_32(struct pt_regs *regs);
 
 #endif	/* CONFIG_X86_32 */
 
+void do_int80_syscall_32(struct pt_regs *regs);
+long do_fast_syscall_32(struct pt_regs *regs);
+long do_SYSENTER_32(struct pt_regs *regs);
+
 #endif	/* _ASM_X86_SYSCALL_H */