loongarch: avoid generating extra header files

The list of generated headers is rather outdated, some of these no longer
exist, while others are already listed in include/asm-generic/Kbuild
so there is no need to list them here.

As we start validating the list of headers against the files that exist,
the outdated ones now cause a warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/loongarch/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 generated-y += orc_hash.h
 
-generic-y += dma-contiguous.h
 generic-y += mcs_spinlock.h
 generic-y += parport.h
 generic-y += early_ioremap.h
 generic-y += qrwlock.h
 generic-y += qspinlock.h
-generic-y += rwsem.h
-generic-y += segment.h
 generic-y += user.h
-generic-y += stat.h
-generic-y += fcntl.h
 generic-y += ioctl.h
-generic-y += ioctls.h
-generic-y += mman.h
-generic-y += msgbuf.h
-generic-y += sembuf.h
-generic-y += shmbuf.h
 generic-y += statfs.h
-generic-y += socket.h
-generic-y += sockios.h
-generic-y += termbits.h
-generic-y += poll.h
 generic-y += param.h
-generic-y += posix_types.h
-generic-y += resource.h