thermal: intel: powerclamp: fix mismatch in get function for max_idle

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

thermal: intel: powerclamp: fix mismatch in get function for max_idle

KASAN reported this

[ 444.853098] BUG: KASAN: global-out-of-bounds in param_get_int+0x77/0x90

[ 444.853111] Read of size 4 at addr ffffffffc16c9220 by task cat/2105

...

[ 444.853442] The buggy address belongs to the variable:

[ 444.853443] max_idle+0x0/0xffffffffffffcde0 [intel_powerclamp]

There is a mismatch between the param_get_int and the definition of

max_idle. Replacing param_get_int with param_get_byte resolves this

issue.