Linux 5.19 compat: zap_flags_t conflict

As of the Linux 5.19 kernel an identically named zap_flags_t typedef
is declared in the include/linux/mm_types.h linux header. Sadly,
the inclusion of this header cannot be easily avoided. To resolve
the conflict a #define is used to remap the name in the OpenZFS
sources when building against the Linux kernel.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13515