coredump: Fix return value in coredump_parse()

coredump: Fix return value in coredump_parse()

The coredump_parse() function is bool type.  It should return true on
success and false on failure.  The cn_printf() returns zero on success
or negative error codes.  This mismatch means that when "return err;"
here, it is treated as success instead of failure.  Change it to return
false instead.

Fixes: a5715af549b2 ("coredump: make coredump_parse() return bool")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/aKRGu14w5vPSZLgv@stanley.mountain
Signed-off-by: Christian Brauner <brauner@kernel.org>