[PATCH 0/4] Fix the x86 defconfig build with GCC 17

[Vineet Gupta <vineet.gupta@linux.dev>]

Fix build warnings and failures (CONFIG_WERROR=y) with a GCC 17 build.
GCC 17 adds -Wconstant-logical-operand which is strict about operands
of && or || that fold to a constant other than 0 or 1.

In the past similar fixes have been done for clang, e.g.

  93f56de25937 2017-04-06 mac80211: Fix clang warning about constant operand in logical operation  [v4.12-rc1]
  ...
  dd7fe5d9fd6a 2024-01-17 rtc: max31335: Fix comparison in max31335_volatile_reg()                 [v6.8-rc1]

The reason this trips only with gcc is that clang's toggle is more
permissive:
 - it checks RHS only, not constant LHS.
 - Macros are not checked.

Fix is to effectively make a macro or condition return 0 or 1.

The patches are split up per subsystem and can go independently via
respective trees:

  1/4 x86/cpufeatures: the awk-generated *_MASK_BIT_SET() returns 0 or 1.
  2/4 wait: ___wait_is_interruptible() with a constant state.
  3/4 iommupt: PT_SUPPORTED_FEATURE() in the fvalog2_*() helpers.
  4/4 drm/i915: IS_POWER_OF_2() in reg_bits.h, and two Kconfig timeouts.

Tested on x86 defconfig with CONFIG_WERROR=y, at each patch:

 - GCC 17 trunk (20261103): each patch removes only its own errors. The
   build has no warnings after 4/4.
 - GCC 16.1: the build has no warnings. The .text of each object file
   does not change. The only differences come from the build timestamp
   and the release string.

Vineet Gupta (4):
  x86/cpufeatures: Make {REQUIRED,DISABLED}_MASK_BIT_SET() return 0 or 1
  wait: Make ___wait_is_interruptible() return 0 or 1
  iommupt: Make PT_SUPPORTED_FEATURE() return 0 or 1
  drm/i915: Avoid -Wconstant-logical-operand with GCC 17

 arch/x86/tools/cpufeaturemasks.awk          | 4 ++--
 drivers/gpu/drm/i915/gem/i915_gem_context.c | 2 +-
 drivers/gpu/drm/i915/i915_config.c          | 2 +-
 drivers/iommu/generic_pt/pt_defs.h          | 2 +-
 include/drm/intel/reg_bits.h                | 2 +-
 include/linux/wait.h                        | 2 +-
 6 files changed, 7 insertions(+), 7 deletions(-)

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