cpufreq: pxa2xx: remove incorrect __init annotation

pxa_cpufreq_init_voltages() is marked __init but usually inlined into
the non-__init pxa_cpufreq_init() function. When building with clang,
it can stay as a standalone function in a discarded section, and produce
this warning:

WARNING: vmlinux.o(.text+0x616a00): Section mismatch in reference from the function pxa_cpufreq_init() to the function .init.text:pxa_cpufreq_init_voltages()
The function pxa_cpufreq_init() references
the function __init pxa_cpufreq_init_voltages().
This is often because pxa_cpufreq_init lacks a __init
annotation or the annotation of pxa_cpufreq_init_voltages is wrong.

Fixes: 50e77fcd ("ARM: pxa: remove __init from cpufreq_driver->init()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>