net: intel: fix old compiler regressions

The kernel build regressions/improvements email contained a couple of
issues with old compilers (in fact all the reports were on different
architectures, but all gcc 5.5) and the FIELD_PREP() and FIELD_GET()
conversions. They're all because an integer #define that should have
been declared as unsigned, was shifted to the point that it could set
the sign bit.

The fix just involves making sure the defines use the "U" identifier on
the constants to make sure they're unsigned. Should make the checkers
happier.

Confirmed with objdump before/after that there is no change to the
binaries.

Issues were reported as follows:
./drivers/net/ethernet/intel/ice/ice_base.c:238:7: note: in expansion of macro 'FIELD_GET'
      (FIELD_GET(GLINT_CTL_ITR_GRAN_25_M, regval) == ICE_ITR_GRAN_US))
       ^
./include/linux/compiler_types.h:435:38: error: call to '__compiletime_assert_1093' declared with attribute error: FIELD_GET: mask is not constant
drivers/net/ethernet/intel/ice/ice_nvm.c:709:16: note: in expansion of macro ‘FIELD_GET’
  orom->major = FIELD_GET(ICE_OROM_VER_MASK, combo_ver);
                ^
./include/linux/compiler_types.h:435:38: error: call to ‘__compiletime_assert_796’ declared with attribute error: FIELD_GET: mask is not constant
drivers/net/ethernet/intel/ice/ice_common.c:945:18: note: in expansion of macro ‘FIELD_GET’
  u8 max_agg_bw = FIELD_GET(GL_PWR_MODE_CTL_CAR_MAX_BW_M,
                  ^
./include/linux/compiler_types.h:435:38: error: call to ‘__compiletime_assert_420’ declared with attribute error: FIELD_GET: mask is not constant
drivers/net/ethernet/intel/i40e/i40e_dcb.c:458:8: note: in expansion of macro ‘FIELD_GET’
  oui = FIELD_GET(I40E_LLDP_TLV_OUI_MASK, ouisubtype);
        ^

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Closes: https://lore.kernel.org/lkml/d03e90ca-8485-4d1b-5ec1-c3398e0e8da@linux-m68k.org/

 #i40e #ice
Fixes: 62589808 ("i40e: field get conversion")
Fixes: 5a259f8e ("ice: field get conversion")
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Link: https://lore.kernel.org/r/20240206022906.2194214-1-jesse.brandeburg@intel.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>