This reverts commit 
da1a3dc0ebb4f9209a1939eaa6b18901e0cd7bc0.
The originally proposed way in the above commit is incorrect. And
there is no easy way to distinguish between pxa25x and pxa26x at
run-time.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
                __cpu_is_pxa25x(read_cpuid_id());       \
        })
 
-extern int cpu_is_pxa26x(void);
-
 #define cpu_is_pxa27x()                                        \
        ({                                              \
                __cpu_is_pxa27x(read_cpuid_id());       \
 
 #include "devices.h"
 #include "clock.h"
 
-int cpu_is_pxa26x(void)
-{
-       return cpu_is_pxa250() && ((BOOT_DEF & 0x8) == 0);
-}
-EXPORT_SYMBOL_GPL(cpu_is_pxa26x);
-
 /*
  * Various clock factors driven by the CCCR register.
  */
        }
 
        /* Only add HWUART for PXA255/26x; PXA210/250 do not have it. */
-       if (cpu_is_pxa255() || cpu_is_pxa26x()) {
+       if (cpu_is_pxa255()) {
                clks_register(&pxa25x_hwuart_clk, 1);
                ret = platform_device_register(&pxa_device_hwuart);
        }