Fix some memory problems

[mrdude2478]

Problem - allocated 256MB of memory for the payload,

Location: patch_kernel()

Current code:

const max_size = 0x10000000;  // 256MB - WAY too big

Bad Code Section:

const max_size = 0x10000000;
    if (map_size > max_size) {
        die(`patch file too large (>${max_size}): ${map_size}`);
    }
    if (map_size === 0) {
        die('patch file size is zero');
    }
    map_size = map_size+page_size & -page_size;

Fix: Calculate exact size needed instead of fixed 256MB

let map_size = patches.size;
const max_size = 0x200000;  // 2MB max (adjust if your payload is larger)
if (map_size > max_size) {
    die(`patch file too large (>${max_size}): ${map_size}`);
}
if (map_size === 0) {
    die("patch file size is zero");
}
log(`kpatch size: ${map_size} bytes`);
// Round up to page size
map_size = (map_size + page_size - 1) & ~(page_size - 1);
// Ensure minimum viable size for shellcode
if (map_size < 0x1000) map_size = 0x1000;

Result - reduced out of memory issues.