brcmfmac: extend brcmf_term_iscan() to abort e-scan

With the introduction of E-Scan there are two scan mechanisms
in the driver. I-Scan was aborted on suspend and bringing down
the device using brcmf_term_iscan(). The function has been
renamed to brcmf_abort_scanning() and covers e-scan abort as
well.

Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>