acpi: specify exact minimum dependency versions

This is apparently better practice.

acpi/Cargo.toml

@@ -10,8 +10,8 @@ license = "MIT/Apache-2.0"
 edition = "2018"
 
 [dependencies]
-bit_field = "0.10"
-log = "0.4"
+bit_field = "0.10.2"
+log = "0.4.20"
 rsdp = { version = "2", path = "../rsdp" }
 
 [features]