microblaze: Remove unused boot_cpuid variable

boot_cpuid is not used on uni processor system that's why can be removed.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Stefan Asserhall <stefan.asserhall@xilinx.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

arch/microblaze/include/asm/setup.h

@@ -10,8 +10,6 @@
 #include <uapi/asm/setup.h>
 
 # ifndef __ASSEMBLY__
-extern unsigned int boot_cpuid; /* move to smp.h */
-
 extern char cmd_line[COMMAND_LINE_SIZE];
 
 extern char *klimit;

arch/microblaze/kernel/setup.c

@@ -41,7 +41,6 @@ DEFINE_PER_CPU(unsigned int, ENTRY_SP);	/* Saved SP on kernel entry */
 DEFINE_PER_CPU(unsigned int, R11_SAVE);	/* Temp variable for entry */
 DEFINE_PER_CPU(unsigned int, CURRENT_SAVE);	/* Saved current pointer */
 
-unsigned int boot_cpuid;
 /*
  * Placed cmd_line to .data section because can be initialized from
  * ASM code. Default position is BSS section which is cleared