doc:it_IT: align Italian translation

Translation for the following patches:

commit c4f4af40 ("docs: Add documentation for Symbol Namespaces")
commit 36bc683d ("kernel-doc: rename the kernel-doc directive 'functions' to 'identifiers'")
commit a035d552 ("Makefile: Globally enable fall-through warning")
commit b9918bdc ("Documentation/process: Add fallthrough pseudo-keyword")
commit 58ad30cf ("docs: fix reference to core-api/namespaces.rst")
commit fb0e0ffe ("Documentation: bring process docs up to date")
commit 7af51678 ("docs: deprecated.rst: Add BUG()-family")
commit 7929b983 ("docs: Remove :c:func: from process/deprecated.rst")
commit 76136e02 ("docs: deprecated.rst: Clean up fall-through details")
commit d8401f50 ("docs: deprecated.rst: Add %p to the list")
commit b1735296 ("docs: locking: Drop :c:func: throughout")
commit 6adb7755 ("docs: locking: Add 'need' to hardirq section")

Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
Link: https://lore.kernel.org/r/20200430222037.4480-1-federico.vaga@vaga.pv.it


Signed-off-by: Jonathan Corbet <corbet@lwn.net>