The acquisition of Altera, which makes programmable chips widely used in cellphone towers, the military and other industrial applications, would underscore Intel Chief Executive Officer Brian Krzanich’s determination to expand into new markets as the personal computer industry loses steam. Earlier this month, Intel slashed nearly $1 billion from its first-quarter revenue forecast to $12.8 billion, plus or minus $300 million, as small businesses put off upgrading their personal computers.