asm-generic: Remove asm-generic arch_bprm_mm_init()

This is a follow-on to commit 62e88b1c00de 'mm: Make
arch_unmap()/bprm_mm_init() available to all architectures'

I removed the asm-generic version of arch_unmap() in that patch,
but missed arch_bprm_mm_init(). So this broke the build for
architectures using asm-generic/mmu_context.h who actually have
an MMU.

Fixes: 62e88b1c00de 'mm: Make arch_unmap()/bprm_mm_init() available to all architectures'
Signed-off-by: Dave Hansen <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Thomas Gleixner <[e-mail]>

include/asm-generic/mmu_context.h

···
 {
 }
 
-static inline void arch_bprm_mm_init(struct mm_struct *mm,
-			struct vm_area_struct *vma)
-{
-}
-
 #endif /* __ASM_GENERIC_MMU_CONTEXT_H */