ceph: Use no_printk() helper

When printk-indexing is enabled, each printk() invocation emits a
pi_entry structure.  This is even true when the call is protected by an
always-false check: while the actual code to print the message is
optimized out by the compiler, the pi_entry structure is still emitted.

Fix this by replacing "if (0) printk(...)" constructs by calls to the
no_printk() helper.

This reduces the size of an arm64 kernel with CONFIG_PRINTK_INDEX=y and
CONFIG_CEPH_FS=y by ca. 4 KiB.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/a21767eccb823435a7f18cdf115d7d572b4e945d.1709127473.git.geert+renesas@glider.be


Signed-off-by: Petr Mladek <pmladek@suse.com>