configure: remove default CROSS for arm targets

arm-none-linux-gnueabi- is an anachronism and makes building on native
arm platforms more difficult. further, many distros include alternative
cross compilers, e.g., arm-linux-gnueabihf-, so the choice is best left
up to the user.

Change-Id: Id8aaf820ed112b85db2b8518d0e9d8abee1ad85c
1 file changed