[RFC PATCH net-next v2] ppp: don't store tx skb in the fastpath

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Content preview:  Currently, ppp->xmit_pending is used in ppp_send_frame() to
   pass a skb to ppp_push(), and holds the skb when a PPP channel cannot immediately
   transmit it. This state is redundant because the transmit [...] 

Content analysis details:   (5.0 points, 5.0 required)

 pts rule name              description
---- ---------------------- --------------------------------------------------
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 0.0 DKIM_ADSP_CUSTOM_MED   No valid author signature, adsp_override is
                             CUSTOM_MED
 1.0 FORGED_GMAIL_RCVD      'From' gmail.com does not match 'Received'
                            headers
 0.0 FREEMAIL_FROM          Sender email is commonly abused enduser mail
                            provider (dqfext[at]gmail.com)
 0.2 HEADER_FROM_DIFFERENT_DOMAINS From and EnvelopeFrom 2nd level
                            mail domains are different
 1.3 RCVD_IN_RP_RNBL        RBL: Relay in RNBL,
                            https://senderscore.org/blacklistlookup/
                          [172.105.105.114 listed in bl.score.senderscore.com]
 0.1 DKIM_SIGNED            Message has a DKIM or DK signature, not necessarily
                            valid
 0.0 T_DKIM_INVALID         DKIM-Signature header exists but is not valid
-1.0 MAILING_LIST_MULTI     Multiple indicators imply a widely-seen list
                            manager
 0.0 FREEMAIL_FORGED_FROMDOMAIN 2nd level domains in From and
                            EnvelopeFrom freemail headers are
                            different