PCI: Fix reset_method_store() memory leak

In the Linux kernel, the following vulnerability has been resolved:

PCI: Fix reset_method_store() memory leak

In reset_method_store(), a string is allocated via kstrndup() and assigned

to the local "options". options is then used in with strsep() to find

spaces:

while ((name = strsep(&options, " ")) != NULL) {

If there are no remaining spaces, then options is set to NULL by strsep(),

so the subsequent kfree(options) doesn't free the memory allocated via

kstrndup().

Fix by using a separate tmp_options to iterate with strsep() so options is

preserved.