hexagon: vm_fault: include asm/vm_fault.h for prototypes

hexagon: vm_fault: include asm/vm_fault.h for prototypes

Clang warns:

  arch/hexagon/mm/vm_fault.c:157:6: warning: no previous prototype for function 'read_protection_fault' [-Wmissing-prototypes]
    157 | void read_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:157:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    157 | void read_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:164:6: warning: no previous prototype for function 'write_protection_fault' [-Wmissing-prototypes]
    164 | void write_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:164:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    164 | void write_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:171:6: warning: no previous prototype for function 'execute_protection_fault' [-Wmissing-prototypes]
    171 | void execute_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:171:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    171 | void execute_protection_fault(struct pt_regs *regs)
        | ^
        | static

The prototypes for these functions are defined in asm/vm_fault.h, so
include it to pick them up and silence the warnings.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-6-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>