First, it is not CHARGER, it is an AC-DC adapter.
Then, if the 90-W adapter is of the same brand as the original 130-W adapter, and all are for the same laptop brand and have interchangeable barrel plug, the laptop must be able to detect the adapter properties, and scale down its consumption, and likely limit internal charging rate and limit any turbo modes the laptop can execute. This is the normal case scenario.
Usually a normal laptop will report what kind of power adapter is connected, somewhere in general properties of "ACPI battery", or through some laptop-specific applet.
In worst case your "a laptop" will determine that the 90-W power of this adapter is insufficient and won't accept any charge. Your laptop will operate on internal battery and drain it totally, eventually.
From your comment it looks like you have the normal scenario, so you should be just fine.