[GIT PULL] build: Pass env CFLAGS through to make

[phlax]

In our (envoy) build we use a sysroot to ensure hermetic builds.

This fixes a problem where configure is passed the sysroot flag and detects kernel headers for openat2.h but then make doesnt have the sysroot and fails.

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git request-pull output:

The following changes since commit 4235cf5db414884887e4b5599311c59c31d71085:

  test: remove t_sqe_prep_cmd() (2025-10-24 12:27:09 -0600)

are available in the Git repository at:

  origin/make-cflags 

for you to fetch changes up to 28123d5ef766c5d0dc5604187dfe57d624205dcf:

  build: Pass env CFLAGS through to make (2025-12-12 12:54:13 +0000)

----------------------------------------------------------------
Ryan Northey (1):
      build: Pass env CFLAGS through to make

 configure    | 10 ++++++++--
 src/Makefile |  2 +-
 2 files changed, 9 insertions(+), 3 deletions(-)

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src/queue: don't flush SQ ring for new wait interface

If we have IORING_FEAT_EXT_ARG, then timeouts are done through the
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Fixes: https://github.com/axboe/liburing/issues/402
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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