ARM: 8752/1: Kconfig: default ARM_MODULE_PLTS to 'y'

While testing multi_v7_defconfig with config fragments that makes the
kernel size to grow. The kernel fails to load simple modules, as
reported by kselftest:

[   34.107620] test_printf: section 4 reloc 2 sym 'memset': relocation
28 out of range (0xbf046044 -> 0xc109f720)
selftests: printf.sh [FAIL]

The problem that is seen when enabling too much in the kernel without
enabling ARM_MODULE_PLTS, is that the top of the kernel gets out of
reach from the bottom of the module area.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>