MIPS: don't include <linux/genhd.h> in <asm/mach-rc32434/rb.h>

There is no need to include genhd.h from a random arch header, and not
doing so prevents the possibility for nasty include loops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210727055646.118787-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

arch/mips/include/asm/mach-rc32434/rb.h

@@ -7,8 +7,6 @@
 #ifndef __ASM_RC32434_RB_H
 #define __ASM_RC32434_RB_H
 
-#include <linux/genhd.h>
-
 #define REGBASE		0x18000000
 #define IDT434_REG_BASE ((volatile void *) KSEG1ADDR(REGBASE))
 #define UART0BASE	0x58000