Revert "omap4-common/umts_spyder: edit RIL to use 255.255.255.252 as netmask"

Handle wrong netmasks in the kernel, where it is not so
fragile and can even work correctly for the LTE-interface.

This reverts commit 5020b6a876cb68e08aa77f7a4d1d5e95ce1881f8 and
commit 2eac6faf3807a90422d86f54ca750607393cac9f.

Change-Id: Ic9cb014950765092f29a2e97279097e85df9799d