net: ipa: Fix double free of the interrupt structure on config error

Since ipa_interrupt_init() allocates struct ipa_interrupt in ipa_probe(),
the structure is owned by ipa_probe() and released with
ipa_interrupt_exit() on its error paths and in ipa_remove().  The error
path of ipa_interrupt_config() still frees it with kfree().  If
ipa_interrupt_config() fails (called from ipa_config() via ipa_setup()),
ipa_probe() unwinds through err_interrupt_exit, which frees the same
structure again.

Drop the kfree() from ipa_interrupt_config(); it should only undo what it
set up itself. Drop the leftover initialization and cleanup of
ipa->interrupt now managed in ipa_proble() and ipa_remove() of ipa_main.c.

Fixes: ad1be80d7582 ("net: ipa: introduce ipa_interrupt_init()")
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Reviewed-by: Alex Elder <elder@riscstar.com>
Link: https://patch.msgid.link/20261029082100.17722-2-fourier.thomas@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>