Remove unsupported -auto icx flag from Intel oneAPI stanza

[islas]

TYPE: bug fix

KEYWORDS: intel, compilation, oneapi

SOURCE: internal

DESCRIPTION OF CHANGES: Problem: The -auto flag is not supported by the Intel C compilers. See https://www.intel.com/content/www/us/en/docs/cpp-compiler/developer-guide-reference/2021-10/alphabetical-option-list.html for full list of supported icx flags.

Solution: Remove the flag, no output changes should happen as the flag was previously being ignored if it didn't cause an error.