console: Fix CONSOLE_NONE support ...

Without console support we need a static inline version of
pr_print and dev_printf, otherwise we get link errors.

Reported-by: Kevin Du Huanpeng <u74147@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Introduce message logging support ...

This adds a buffer for log messages and a 'dmesg' command to
print the messages. The log buffer is implemented as log objects
rather than a string buffer. This makes it easy to implement
limiting the messages, cleaning the buffer and timestamping
the messages.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

introduce verbose debug ...

During debugging it sometimes helps to me even more verbose. This
adds an additional debug level for this. Also we remove an already
existing pr_vdebug definition in the USB gadget u_serial driver.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

introduce runtime loglevel ...

With this the verbosity of barebox can be controlled during runtime
using the 'loglevel' globalvar.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

include/printk: fix level of pr_err and pr_warning ...

The level of pr_err and pr_warning were interchanged.

Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fix another brown paper bag bug introduced with compile time loglevel ...

__pr_printk is a define which uses a local variable 'ret'. This
means that whenever someone does a pr_*("ret: %d\n", ret);
ret will be 0.

Fix this by writing this without a local variable.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fix brown paper bag bug introduced with compile time loglevel ...

__dev_printf is a define which uses a local variable 'ret'. This
means that whenever someone does a dev_*(dev, "ret: %d\n", ret);
ret will be 0.

Fix this by writing this without a local variable.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

introduce pr_fmt ...

With this the files can give more context to their pr_* messages by
specifying a

at the beginning of the files. Basically the same mechanism as in the
Kernel.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

introduce compile time loglevel ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

consolidate print* in a single header ...

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>