bitbake: providers.py: print a debug message for dynamic pacakge

We can't know the dynamic pacakge's name exactly, there might be a
problem, for example, when we use:

IMAGE_INSTALL_append += "ncurses-lib12344"

The ncurses-lib12344 matches ncurses' dynamic packages pattern:

PACKAGES_DYNAMIC = "^${PN}-lib.*"

so there is no errors before the rootfs creation though there is no
ncurses-lib12344.

We can warn this, but I think that we'd better not since there are many
dynamic packages, or there would be too many warnings, for example, the
perl and kernel modules, maybe we can print a debug message for it.

[YOCTO #4798]

(Bitbake rev: df372ca057f0c8c2152223b3e26ad9a30958bab6)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/providers.py

@@ -376,5 +376,6 @@ def getRuntimeProviders(dataCache, rdepend):
             regexp_cache[pattern] = regexp
         if regexp.match(rdepend):
             rproviders += dataCache.packages_dynamic[pattern]
+            logger.debug(1, "Assuming %s is a dynamic package, but it may not exist" % rdepend)
 
     return rproviders