configure: inconsistent configure option "get-easy-option"

[Bastian-Krause]

Hi,

the help text and the configure option get-easy-option/get-easy-options are inconsistent:

curl/configure.ac

Lines 3803 to 3809 in a3a298d

	dnl ************************************************************
	dnl disable the curl_easy_options API
	dnl
	AC_MSG_CHECKING([whether to support curl_easy_option*])
	AC_ARG_ENABLE(get-easy-option,
	AS_HELP_STRING([--enable-get-easy-options],[Enable curl_easy_options])
	AS_HELP_STRING([--disable-get-easy-options],[Disable curl_easy_options]),

I am not sure which variant is correct here, so I'm opening this issue instead of a PR.

[bagder]

Since this sets the define CURL_DISABLE_GETOPTIONS with a plural s, maybe go with that for all of them?